Document:

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                                                                    Exhibit 10.6

                          REGISTRATION RIGHTS AGREEMENT

      REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of March 12,
2003, by and among Hemispherx Biopharma, Inc., a Delaware corporation, with
headquarters located at One Penn Center, 1617 JFK Boulevard, Suite 660,
Philadelphia, PA 19103 (the "Company"), and the undersigned buyers (each, a
"Buyer" and collectively, the "Buyers").

      WHEREAS:

      A. In connection with the Securities Purchase Agreement by and among the
parties hereto of even date herewith (the "Securities Purchase Agreement"), the
Company has agreed, upon the terms and subject to the conditions of the
Securities Purchase Agreement, to issue and sell to the Buyers (i) an aggregate
of $5,426,000 of the Company's 6% Senior Secured Convertible Debentures due
January 31, 2005 (such Senior Secured Convertible Debentures, as the same may be
amended, modified or supplemented from time to time in accordance with the terms
thereof, the "Convertible Debentures"), which will be convertible into shares of
the Company's common stock, par value $0.001 per share (the "Common Stock") (as
converted, the "Conversion Shares"), and (ii) warrants (the "Warrants") to
purchase shares of Common Stock (as exercised collectively, the "Warrant
Shares");

      B. To induce the Buyers to execute and deliver the Securities Purchase
Agreement, the Company has agreed to provide certain registration rights to the
Buyers under the Securities Act of 1933, as amended, and the rules and
regulations thereunder, or any similar successor statute (collectively, the
"1933 Act"), and applicable state securities laws; and

      C. The location of defined terms in this Agreement is set forth on the
Index of Terms attached hereto.

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and each of the Buyers
hereby agree as follows:

      1. Definitions. As used in this Agreement, the following terms shall have
the following meanings:

            a. "Business Day" means any day other than Saturday, Sunday or any
other day on which commercial banks in The City of New York are authorized or
required by law to remain closed.

            b. "Investor" means a Buyer, any transferee or assignee thereof to
whom a Buyer assigns its rights under this Agreement and who agrees to become
bound by the provisions of this Agreement in accordance with Section 9 and any
transferee or assignee thereof to whom a transferee or assignee assigns its
rights under this Agreement and who agrees to become bound by the provisions of
this Agreement in accordance with Section 9.

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            c. "Person" means an individual, a limited liability company, a
partnership, a joint venture, a corporation, a trust, an unincorporated
organization and governmental or any department or agency thereof.

            d. "register" "registered," and "registration" refer to a
registration effected by preparing and filing one or more Registration
Statements (as defined below) in compliance with the 1933 Act and pursuant to
Rule 415 under the 1933 Act or any successor rule providing for offering
securities on a continuous or delayed basis ("Rule 415"), and the declaration or
ordering of effectiveness of such Registration Statement(s) by the United States
Securities and Exchange Commission (the "SEC").

            e. "Registrable Securities" means (i) the Warrant Shares issued or
issuable upon exercise of all of the Warrants, (ii) the Conversion Shares issued
or issuable upon conversion of all of the Convertible Debentures, (iii) the
Interest Shares and the Repayment Shares (each, as defined in the Convertible
Debentures) issued or issuable on the Convertible Debentures and (iv) any shares
of capital stock issued or issuable with respect to the Warrant Shares, the
Conversion Shares, the Convertible Debentures, the Interest Shares, or the
Repayment Shares as a result of any stock split, stock dividend,
recapitalization, exchange or similar event or otherwise, without regard to any
limitations on conversions of Convertible Debentures or the exercise of the
Warrants; provided, however, that shares of Common Stock which are Registrable
Securities shall cease to be Registrable Securities (A) upon any sale pursuant
to a Registration Statement, Rule 144 under the 1933 Act or upon any sale in any
manner to a person or entity which, by virtue of Section 9 of this Agreement, is
not entitled to the rights provided in this Agreement or (B) at such time as all
such shares may be sold under Rule 144(k).

            f. "Registration Statement" means a registration statement or
registration statements of the Company filed under the 1933 Act covering the
Registrable Securities.

      Capitalized terms used herein and not otherwise defined herein shall have
the respective meanings set forth in the Securities Purchase Agreement.

      2. Registration.

            a. Mandatory Registration. The Company shall prepare and, as soon as
practicable but in no event later than the earlier of (x) the date on which the
Company files the Company's Annual Report on Form 10-K for the year ended
December 31, 2002 and (y) March 31, 2003 (such earlier date being the "Filing
Deadline"), file with the SEC the Registration Statement on Form S-3 covering
the resale of all of the Registrable Securities. In the event that Form S-3 is
unavailable for such a registration, the Company shall use such other form as is
available for such a registration, subject to the provisions of Section 2(d), in
which case the "Filing Deadline" shall be forty-five (45) days after the Closing
Date. The Registration Statement prepared pursuant hereto shall register for
resale at least 6,971,256 shares of Common Stock, subject to adjustment as
provided in Section 2(e). The Company shall use its best efforts to have the
Registration Statement declared effective by the SEC as soon as practicable, but
in no event later than the date which is seventy-five (75) days after the
Closing Date. Until such time as the Registration Statement is declared
effective by the SEC, the Company shall not file with

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the SEC any other registration statement under the 1933 Act with respect to the
resale or initial issuance of any Company securities.

            b. Allocation of Registrable Securities. The initial number of
Registrable Securities included in any Registration Statement and each increase
in the number of Registrable Securities included therein shall be allocated pro
rata among the Investors based on the number of Registrable Securities held by
each Investor at the time the Registration Statement covering such initial
number of Registrable Securities or increase thereof is declared effective by
the SEC. Subject to Section 9, in the event that an Investor sells or otherwise
transfers any of such Investor's Registrable Securities, each transferee shall
be allocated the portion of the then remaining number of Registrable Securities
included in such Registration Statement allocable to the transferor. The Company
shall not include any securities other than Registrable Securities on any
Registration Statement without the prior written consent of Buyers holding at
least 60% of Registrable Securities.

            c. Legal Counsel. Subject to Section 5 hereof, the Buyers holding at
least 60% of the Registrable Securities shall have the right to select one legal
counsel to review and comment upon any registration pursuant to this Section 2
("Legal Counsel"), which shall be Schulte Roth & Zabel LLP or such other counsel
as thereafter designated in writing by the holders of at least 60% of the
Registrable Securities.

            d. Ineligibility for Form S-3. In the event that Form S-3 is not
available for the registration of the resale of Registrable Securities
hereunder, the Company shall (i) register the resale of the Registrable
Securities on another appropriate form reasonably acceptable to the holders of
at least 60% of the Registrable Securities and (ii) undertake to register the
Registrable Securities on Form S-3 as soon as such form is available, provided
that the Company shall maintain the effectiveness of the Registration Statement
then in effect until such time as a Registration Statement on Form S-3 covering
the Registrable Securities has been declared effective by the SEC.

            e. Sufficient Number of Shares Registered. In the event the number
of shares available under a Registration Statement filed pursuant to Section
2(a) is insufficient to cover all of the Registrable Securities required to be
covered by such Registration Statement or an Investor's allocated portion of the
Registrable Securities pursuant to Section 2(b), the Company shall amend the
Registration Statement, or file a new Registration Statement (on the short form
available therefor, if applicable), or both, so as to cover at least 135% of the
number of such Registrable Securities as of the trading day immediately
preceding the date of the filing of such amendment or new Registration
Statement, in each case, as soon as practicable, but in any event not later than
fifteen (15) days after the necessity therefor arises. The Company shall use its
best efforts to cause such amendment and/or new Registration Statement to become
effective as soon as practicable following the filing thereof. The calculation
of the number of shares sufficient to cover all of the Registrable Securities
shall be made without regard to any limitations on the conversion of the
Convertible Debentures or the exercise of the Warrants, and such calculation
shall assume that the Convertible Debentures and the Warrants are then
convertible into shares of Common Stock and the maximum number of Interest
Shares and Repayment Shares under the Convertible Debentures, assuming the
initial outstanding principal amount of the Convertible Debentures remains
outstanding through the scheduled maturity date

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and assuming no conversions or redemptions of the Convertible Debentures prior
to the scheduled maturity date, are issuable at the then prevailing Conversion
Rate (as defined in the Convertible Debentures), Warrant Exercise Price (as
defined in the Warrants), Interest Share Conversion Rate (as defined in the
Convertible Debentures), or Equity Collateral conversion Rate (as defined in the
Convertible Debentures), as applicable.

            f. Effect of Failure to File and Obtain and Maintain Effectiveness
of Registration Statement. If (i) a Registration Statement covering all the
Registrable Securities required to be covered thereby and required to be filed
by the Company pursuant to this Agreement is (A) not filed with the SEC on or
before the Filing Deadline, or (B) not declared effective by the SEC on or
before the date that is ninety (90) days after the Closing Date (the
"Effectiveness Deadline") or (ii) on any day after such Registration Statement
has been declared effective by the SEC sales of all the Registrable Securities
required to be included on such Registration Statement cannot be made (other
than during an Allowable Grace Period (as defined in Section 3(p)) pursuant to
such Registration Statement (including, without limitation, because of a failure
to keep such Registration Statement effective, to disclose such information as
is necessary for sales to be made pursuant to such Registration Statement or to
register sufficient shares of Common Stock), then, as partial relief for the
damages to any holder by reason of any such delay in or reduction of its ability
to sell the underlying shares of Common Stock (which remedy shall not be
exclusive of any other remedies available at law or in equity), the Company
shall pay to each holder of Convertible Debentures relating to such Registration
Statement an amount in cash equal to the product of (i) the outstanding
principal amount of such Investor's Convertible Debentures to which the
Registration Statement relates multiplied by (ii) the product of (I) .00067
multiplied by (II) the sum of (x) the number of days after the applicable Filing
Deadline that the Registration Statement is not filed with the SEC, plus (y) the
number of days after the applicable Effectiveness Deadline that the Registration
Statement is not declared effective by the SEC, plus (z) the number of days, in
each instance, after the Registration Statement has been declared effective by
the SEC that such Registration Statement is not available (other than during an
Allowable Grace Period) for the sale of all the Registrable Securities required
to be included on such Registration Statement. The payments to which a holder
shall be entitled pursuant to this Section 2(f) are referred to herein as
"Registration Delay Payments." Registration Delay Payments shall be paid on the
earlier of (I) the last day of the calendar month during which such Registration
Delay Payments are incurred and (II) the third Business Day after the event or
failure giving rise to the Registration Delay Payments is cured. In the event
the Company fails to make Registration Delay Payments in a timely manner, such
Registration Delay Payments shall bear interest at the rate of 1.5% per month
(prorated for partial months) until paid in full.

      3. Related Obligations.

      At such time as the Company is obligated to file a Registration Statement
with the SEC pursuant to Section 2(a), 2(d) or 2(e), the Company will use its
best efforts to effect the registration of the Registrable Securities in
accordance with the intended method of disposition thereof and, pursuant
thereto, the Company shall have the following obligations:

            a. The Company shall promptly prepare and file with the SEC a
Registration Statement with respect to the Registrable Securities (but in no
event later than the

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applicable Filing Deadline) and use its best efforts to cause such Registration
Statement relating to the Registrable Securities required to be covered thereby
to become effective as soon as practicable after such filing (but in no event
later than the date which is ninety (90) days after the Closing Date). The
Company shall, subject to the terms of this Agreement, keep each Registration
Statement effective pursuant to Rule 415 at all times until the earlier of (i)
the date as of which the Investors may sell all of the Registrable Securities
covered by such Registration Statement without restriction pursuant to Rule
144(k) (or successor thereto) promulgated under the 1933 Act or (ii) the date on
which the Investors shall have sold all the Registrable Securities covered by
such Registration Statement (the "Registration Period"), which Registration
Statement, as of its filing date, (including any amendments or supplements
thereto and prospectuses contained therein, as of their respective filing dates)
shall not contain any untrue statement of a material fact or omit to state a
material fact required to be stated therein, or necessary to make the statements
therein, in light of the circumstances in which they were made, not misleading.
The term "best efforts" shall mean, among other things, that the Company shall
submit to the SEC, within five (5) Business Days after the Company learns that
no review of a particular Registration Statement will be made by the staff of
the SEC or that the staff has no further comments on the Registration Statement,
as the case may be, and the approval of Legal Counsel pursuant to Section 3(c),
a request for acceleration of effectiveness of such Registration Statement to a
time and date not later than 48 hours after the submission of such request.

            b. Subject to Section 3(p), the Company shall prepare and file with
the SEC such amendments (including post-effective amendments) and supplements to
the Registration Statement and the prospectus used in connection with such
Registration Statement, which prospectus is to be filed pursuant to Rule 424
promulgated under the 1933 Act, as may be necessary to keep such Registration
Statement effective at all times during the Registration Period, and, during
such period, comply with the provisions of the 1933 Act applicable to the
Company with respect to the disposition of all Registrable Securities covered by
such Registration Statement until such time as all of such Registrable
Securities shall have been disposed of in accordance with the intended methods
of disposition by the seller or sellers thereof as set forth in such
Registration Statement. In the case of amendments and supplements to a
Registration Statement which are required to be filed pursuant to this Agreement
(including pursuant to this Section 3(b)) by reason of the Company filing a
report on Form 10-K, Form 10-Q or Form 8-K or any analogous report under the
Securities Exchange Act of 1934, as amended (the "1934 Act"), the Company shall
have incorporated such report by reference into such Registration Statement, if
applicable, or shall file such amendments or supplements with the SEC on the
same day on which the 1934 Act report is filed which created the requirement for
the Company to amend or supplement such Registration Statement.

            c. The Company shall permit Legal Counsel to review and comment upon
(i) a Registration Statement at least three (3) Business Days prior to its
filing with the SEC and (ii) all other Registration Statements and all
amendments and supplements thereto (except for Annual Reports on Form 10-K,
Quarterly Reports on Form 10-Q and Current Reports on Form 8-K and any similar
or successor reports or other documents incorporated by reference therein)
within a reasonable number of days prior to their filing with the SEC. The
Company shall furnish to Legal Counsel, without charge, (i) copies of any
correspondence from the SEC or the staff of the SEC to the Company or its
representatives relating to any Registration Statement, (ii) promptly after the
same is prepared and filed with the SEC, one copy of any Registration

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Statement and any amendment(s) thereto, including financial statements (but
excluding all schedules, all documents incorporated therein by reference, and
all exhibits, unless requested in writing by Legal Counsel) and (iii) upon the
effectiveness of any Registration Statement, one copy of the prospectus included
in such Registration Statement and all amendments and supplements thereto. The
Company agrees that it will, and it will cause its counsel to, consider in good
faith any comments or objections from Legal Counsel as to the form or content of
any Registration Statement or amendments or supplements thereto or any request
for acceleration of the effectiveness of any Registration Statement or any
amendment or supplement thereto.

            d. The Company shall furnish to each Investor whose Registrable
Securities are included in any Registration Statement, without charge, (i)
promptly after the same is prepared and filed with the SEC, at least one copy of
such Registration Statement and any amendment(s) thereto, including financial
statements (but excluding all schedules, all documents incorporated therein by
reference and all exhibits, unless requested in writing by Legal Counsel) and
each preliminary prospectus, (ii) upon the effectiveness of any Registration
Statement, ten (10) copies of the prospectus included in such Registration
Statement and all amendments and supplements thereto (or such other number of
copies as such Investor may reasonably request) and (iii) such other documents,
including copies of any preliminary or final prospectus, as such Investor may
reasonably request from time to time in order to facilitate the disposition of
the Registrable Securities owned by such Investor.

            e. Subject to Section 3(p), the Company shall use its best efforts
to (i) register and qualify, unless an exemption from registration and
qualification applies, the resale by Investors of the Registrable Securities
covered by the Registration Statement under such other securities or "blue sky"
laws of all applicable jurisdictions in the United States as any holder of
Registrable Shares reasonably requests in writing, (ii) prepare and file in
those jurisdictions, such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; provided, however, that
the Company shall not be required in connection therewith or as a condition
thereto to (x) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(e), (y) subject itself
to general taxation in any such jurisdiction, or (z) file a general consent to
service of process in any such jurisdiction. The Company shall promptly notify
Legal Counsel and each Investor who holds Registrable Securities of the receipt
by the Company of any notification with respect to the suspension of the
registration or qualification of any of the Registrable Securities for sale
under the securities or "blue sky" laws of any jurisdiction in the United States
or its receipt of actual notice of the initiation or threatening of any
proceeding for such purpose.

            f. Notwithstanding anything to the contrary set forth herein, as
promptly as practicable after becoming aware of such event, the Company shall
notify Legal Counsel and each Investor in writing of the happening of any event,
of which the Company has knowledge, as a result of which the prospectus included
in a Registration Statement, as then in effect, includes an untrue statement of
a material fact or omission to state a material fact required to be stated
therein or necessary to make the statements therein, in light of the
circumstances under which

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they were made, not misleading (provided that in no event shall such notice
contain any material, nonpublic information), and, subject to Section 3(p),
promptly prepare a supplement or amendment to such Registration Statement to
correct such untrue statement or omission, and deliver ten (10) copies of such
supplement or amendment to Legal Counsel and each Investor (or such other number
of copies as Legal Counsel or such Investor may reasonably request). The Company
shall also promptly notify Legal Counsel and each Investor in writing (i) when a
prospectus or any prospectus supplement or post-effective amendment has been
filed, and when a Registration Statement or any post-effective amendment has
become effective (notification of such effectiveness shall be delivered to Legal
Counsel and each Investor by facsimile on the same day of such effectiveness and
by overnight mail), (ii) of any request by the SEC for amendments or supplements
to a Registration Statement or related prospectus or related information, and
(iii) of the Company's reasonable determination that a post-effective amendment
to a Registration Statement would be appropriate.

            g. Subject to Section 3(p), the Company shall use its best efforts
to (i) prevent the issuance of any stop order or other suspension of
effectiveness of a Registration Statement, or the suspension of the
qualification of any of the Registrable Securities for sale in any jurisdiction
and, (ii) if such an order or suspension is issued, to obtain the withdrawal of
such order or suspension at the earliest practicable moment and to notify Legal
Counsel and each Investor who holds Registrable Securities being sold of the
issuance of such order and the resolution thereof or its receipt of actual
notice of the initiation or threat of any proceeding for such purpose.

            h. Notwithstanding the provisions of Section 4(h) of the Securities
Purchase Agreement, the Company shall make available for inspection by (i) any
Investor, (ii) Legal Counsel and (iii) one firm of accountants or other agents
retained by the Investors at the Investors' expense (collectively, the
"Inspectors"), at the offices where normally kept and during reasonable business
hours, all pertinent financial and other records, and pertinent corporate
documents and properties of the Company (collectively, the "Records"), as shall
be reasonably deemed necessary by each Inspector, and cause the Company's
officers, directors and employees to supply all information which any Inspector
may reasonably request; provided, however, that each Inspector shall agree in
writing to hold in strict confidence and shall not make any disclosure (except
to an Investor) or use of any Record or other information that the Company
determines in good faith to be confidential, and of which determination the
Inspectors are so notified, unless (a) the disclosure of such Records is
necessary to avoid or correct a misstatement or omission in any Registration
Statement or is otherwise required under the 1933 Act, (b) the release of such
Records is ordered pursuant to a final, non-appealable subpoena or order from a
court or government body of competent jurisdiction, or (c) the information in
such Records has been made generally available to the public other than by
disclosure in violation of this or any other agreement of which the Inspector
has knowledge. Each Investor agrees that it shall, upon learning that disclosure
of such Records is sought in or by a court or governmental body of competent
jurisdiction or through other means, give prompt notice to the Company and allow
the Company, at its expense, to undertake appropriate action to prevent
disclosure of, or to obtain a protective order for, the Records deemed
confidential. Nothing herein (or in any other confidentiality agreement between
the Company and any Investor) shall be deemed to limit the Investors' ability to
sell Registrable Securities in a manner that is otherwise consistent with
applicable laws and regulations and the terms and provisions of this Agreement.

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            i. The Company shall hold in confidence and not make any disclosure
of information concerning an Investor provided to the Company unless (i)
disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other final,
non-appealable order from a court or governmental body of competent
jurisdiction, or (iv) such information has been made generally available to the
public other than by disclosure in violation of this Agreement or any other
agreement. The Company agrees that it shall, upon learning that disclosure of
such information concerning an Investor is sought in or by a court or
governmental body of competent jurisdiction or through other means, give prompt
written notice to such Investor and allow such Investor, at the Investor's
expense, to undertake appropriate action to prevent disclosure of, or to obtain
a protective order for, such information.

            j. The Company shall use its best efforts either to (i) cause all
the Registrable Securities covered by a Registration Statement to be listed on
each securities exchange on which securities of the same class or series issued
by the Company are then listed, if any, if the listing of such Registrable
Securities is then permitted under the rules of such exchange, or (ii) secure
designation and quotation of all the Registrable Securities covered by a
Registration Statement on The American Stock Exchange or The Nasdaq National
Market, or (iii) if, despite the Company's best efforts to satisfy the preceding
clause (i) or (ii), the Company is unsuccessful in satisfying the preceding
clause (i) or (ii), to secure the inclusion for quotation on the The Nasdaq
SmallCap Market for such Registrable Securities and, without limiting the
generality of the foregoing, to use its best efforts to arrange for at least two
market makers to register with the National Association of Securities Dealers,
Inc. ("NASD") as such with respect to such Registrable Securities. The Company
shall pay all fees and expenses in connection with satisfying its obligation
under this Section 3(j).

            k. In connection with any sale or transfer of Registrable Securities
pursuant to a Registration Statement, the Company shall cooperate with the
Investors who hold Registrable Securities being offered and, to the extent
applicable, facilitate the timely preparation and delivery of certificates (not
bearing any restrictive legend) representing the Registrable Securities to be
offered pursuant to a Registration Statement and enable such certificates to be
in such denominations or amounts, as the case may be, as the Investors may
reasonably request and, subject to compliance with applicable securities laws,
registered in such names as the Investors may request and if such certificates
are to be issued in the name of a Person other than the registered holder of
such Registrable Securities, then the Investor shall give the Company notice at
least two Business Days prior to any sale of the Registrable Securities.

            l. If requested by an Investor, the Company shall (i) as soon as
practicable incorporate in a prospectus supplement or post-effective amendment
to the Registration Statement such information as an Investor reasonably
requests to be included therein relating to the sale and distribution of
Registrable Securities to which the Company does not reasonably object,
including, without limitation, information with respect to the number of
Registrable Securities being offered or sold, the purchase price being paid
therefor and any other terms of the offering of the Registrable Securities to be
sold in such offering; (ii) as soon as practicable make all required filings of
such prospectus supplement or post-effective amendment after being notified of
the matters to be incorporated in such prospectus supplement or post-

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effective amendment; and (iii) as soon as practicable, supplement or make
amendments to any Registration Statement if reasonably requested by an Investor
holding any Registrable Securities and to which the Company does not reasonably
object.

            m. The Company shall make generally available to its security
holders as soon as practical, but not later than ninety (90) days after the
close of the period covered thereby, an earnings statement (in form complying
with, and in the manner provided by, the provisions of Rule 158 under the 1933
Act) covering a twelve-month period beginning not later than the first day of
the Company's fiscal quarter next following the effective date of a Registration
Statement.

            n. The Company shall otherwise use its best efforts to comply with
all applicable rules and regulations of the SEC in connection with any
registration hereunder.

            o. Within two (2) Business Days after a Registration Statement which
covers Registrable Securities is ordered effective by the SEC, the Company shall
deliver, and shall cause legal counsel for the Company to deliver, to the
transfer agent for such Registrable Securities (with copies to the Investors
whose Registrable Securities are included in such Registration Statement)
confirmation that such Registration Statement has been declared effective by the
SEC in the form attached hereto as Exhibit A.

            p. Notwithstanding anything to the contrary herein, at any time
after the Registration Statement has been declared effective by the SEC, the
Company may delay the disclosure of material non-public information concerning
the Company the disclosure of which at the time is not, in the good faith
judgment of the Board of Directors of the Company, in the best interest of the
Company (a "Grace Period"); provided, that the Company shall promptly (i) notify
the Investors in writing of the existence of material non-public information
giving rise to a Grace Period (provided that in each notice the Company will not
disclose the content of such material non-public information to the Investors)
and the date on which the Grace Period will begin, and (ii) notify the Investors
in writing of the date on which the Grace Period ends; and, provided further,
that no Grace Period shall exceed twenty (20) days and during any three hundred
sixty five (365) day period such Grace Periods shall not exceed an aggregate of
forty-five (45) days and the first day of any Grace Period must be at least two
(2) Business Days after the last day of any prior Grace Period (an "Allowable
Grace Period"). For purposes of determining the length of a Grace Period above,
the Grace Period shall begin on and include the date the Investors receive the
notice referred to in clause (i) and shall end on and include the later of the
date the Investors receive the notice referred to in clause (ii) and the date
referred to in such notice. The provisions of Section 3(g) hereof shall not be
applicable during the period of any Allowable Grace Period. Upon expiration of
the Grace Period, the Company shall again be bound by the first sentence of
Section 3(f).

      4. Obligations Of The Investors.

            a. At least seven (7) Business Days prior to the first anticipated
filing date of a Registration Statement, the Company shall notify each Investor
in writing of the information the Company requires from each such Investor if
such Investor elects to have any of such Investor's Registrable Securities
included in such Registration Statement. It shall be a condition precedent to
the obligations of the Company to complete the registration pursuant to

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this Agreement with respect to the Registrable Securities of a particular
Investor that such Investor shall furnish to the Company such information
regarding itself, the Registrable Securities held by it and the intended method
of disposition of the Registrable Securities held by it as shall be reasonably
required to effect the effectiveness of the registration of such Registrable
Securities and shall execute such documents in connection with such registration
as the Company may reasonably request. Each Investor shall promptly notify the
Company of any material change with respect to such information previously
provided to the Company by such Investor.

            b. Each Investor, by such Investor's acceptance of the Registrable
Securities, agrees to cooperate with the Company as reasonably requested by the
Company in connection with the preparation and filing of any Registration
Statement hereunder, unless such Investor has notified the Company in writing of
such Investor's election to exclude all of such Investor's Registrable
Securities from such Registration Statement.

            c. Each Investor agrees that, upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3(g),
Section 3(p) or the first sentence of 3(f), such Investor will immediately
discontinue disposition of Registrable Securities pursuant to any Registration
Statement(s) covering such Registrable Securities until such Investor's receipt
of the copies of the supplemented or amended prospectus contemplated by Section
3(g) or the first sentence of 3(f) or receipt of notice that no supplement or
amendment is required and, if so directed by the Company, such Investor shall
deliver to the Company (at the expense of the Company) or destroy (and deliver
to the Company a certificate of destruction) all copies (other than a single
file copy, which such Investor may keep) in such Investor's possession of the
prospectus covering such Registrable Securities current at the time of receipt
of such notice. Notwithstanding anything to the contrary, subject to compliance
with applicable securities laws, the Company shall cause its transfer agent to
deliver unlegended shares of Common Stock to a transferee of an Investor in
accordance with the terms of the Securities Purchase Agreement, the Convertible
Debenture and/or the Warrant, as applicable, in connection with any sale of
Registrable Securities with respect to which an Investor has entered into a
contract for sale prior to the Investor's receipt of a notice from the Company
of the happening of any event of the kind described in Section 3(g) or the first
sentence of 3(f) and for which the Investor has not yet settled.

      5. Expenses Of Registration.

      All reasonable expenses, other than underwriting discounts and
commissions, incurred in connection with registrations, filings or
qualifications pursuant to Sections 2 and 3, including, without limitation, all
registration, listing and qualifications fees, printers and accounting fees, and
fees and disbursements of counsel for the Company shall be paid by the Company.
The Company shall also reimburse the Investors for the fees and disbursements of
Legal Counsel in connection with registration, filing or qualification pursuant
to Sections 2 and 3 of this Agreement which amount shall be limited to $10,000
for the Registration Statement.

      6. Indemnification.

                                       10
<PAGE>

      In the event any Registrable Securities are included in a Registration
Statement under this Agreement:

            a. To the fullest extent permitted by law, the Company will, and
hereby does, indemnify, hold harmless and defend each Investor, the directors,
officers, members, partners, employees, agents, representatives of, and each
Person, if any, who controls any Investor within the meaning of the 1933 Act or
the 1934 Act (each, an "Indemnified Person"), against any losses, claims,
damages, liabilities, judgments, fines, penalties, charges, costs, reasonable
attorneys' fees, amounts paid in settlement or expenses, joint or several,
(collectively, "Claims") incurred in investigating, preparing or defending any
action, claim, suit, inquiry, proceeding, investigation or appeal taken from the
foregoing by or before any court or governmental, administrative or other
regulatory agency, body or the SEC, whether pending or threatened, whether or
not an indemnified party is or may be a party thereto ("Indemnified Damages"),
to which any of them may become subject insofar as such Claims (or actions or
proceedings, whether commenced or threatened, in respect thereof) arise out of
or are based upon: (i) any untrue statement or alleged untrue statement of a
material fact in a Registration Statement or any post-effective amendment
thereto or in any filing made in connection with the qualification of the
offering under the securities or other "blue sky" laws of any jurisdiction in
which Registrable Securities are offered ("Blue Sky Filing"), or the omission or
alleged omission to state a material fact required to be stated therein or
necessary to make the statements therein not misleading, (ii) any untrue
statement or alleged untrue statement of a material fact contained in any
preliminary prospectus if used prior to the effective date of such Registration
Statement, or contained in the final prospectus (as amended or supplemented, if
the Company files any amendment thereof or supplement thereto with the SEC) or
the omission or alleged omission to state therein any material fact necessary to
make the statements made therein, in light of the circumstances under which the
statements therein were made, not misleading, (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities pursuant to a Registration Statement or (iv) any material violation
of this Agreement (the matters in the foregoing clauses (i) through (iv) being,
collectively, "Violations"). Subject to Section 6(c), the Company shall
reimburse the Indemnified Persons, promptly as such expenses are incurred and
are due and payable, for any reasonable legal fees or other reasonable expenses
incurred by them in connection with investigating or defending any such Claim.
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(a): (i) shall not apply to a Claim by an
Indemnified Person arising out of or based upon a Violation that occurs in
reliance upon and in conformity with information furnished in writing to the
Company by or on behalf of such Indemnified Person expressly for use in
connection with the preparation of the Registration Statement or any such
amendment thereof or supplement thereto, if such prospectus was timely made
available by the Company pursuant to Section 3(d); (ii) with respect to any
preliminary prospectus, shall not inure to the benefit of any such person from
whom the person asserting any such Claim purchased the Registrable Securities
that are the subject thereof (or to the benefit of any person controlling such
person) if the untrue statement or omission of material fact contained in the
preliminary prospectus was corrected in the prospectus, as then amended or
supplemented, if such prospectus was timely made available by the Company
pursuant to Section 3(d); (iii) shall not be available to the extent such Claim
is based on a failure of the Investor to deliver or to cause to be delivered the
prospectus made available by the Company, including a corrected

                                       11
<PAGE>

prospectus, if such prospectus or corrected prospectus was timely made available
by the Company pursuant to Section 3(d) and, in connection with a corrected
prospectus, the Indemnified Person was promptly advised in writing not to use
the incorrect prospectus prior to the use giving rise to a violation and such
Indemnified Person, notwithstanding such advice, used it or failed to deliver
the correct prospectus as required by the 1933 Act and such correct prospectus
was timely made available pursuant to Section 3(d); and (iv) shall not apply to
amounts paid in settlement of any Claim if such settlement is effected without
the prior written consent of the Company, which consent shall not be
unreasonably withheld or delayed. Such indemnity shall remain in full force and
effect regardless of any investigation made by or on behalf of the Indemnified
Person and shall survive the transfer of the Registrable Securities by the
Investors pursuant to Section 9.

            b. In connection with any Registration Statement in which an
Investor is participating, each such Investor agrees severally and not jointly
to indemnify, hold harmless and defend, to the same extent and in the same
manner as is set forth in Section 6(a), the Company, the directors, officers,
members, partners, employees, agents, representatives of and each Person, if
any, who controls the Company within the meaning of the 1933 Act or the 1934 Act
(each, an "Indemnified Party"), against any Claim or Indemnified Damages to
which any of them may become subject, under the 1933 Act, the 1934 Act or
otherwise, insofar as such Claim or Indemnified Damages arise out of or are
based upon any Violation, in each case to the extent, and only to the extent,
that such Violation occurs in reliance upon and in conformity with written
information furnished to the Company by or on behalf of such Investor expressly
for use in connection with such Registration Statement; and, subject to Section
6(c), such Investor will reimburse any legal or other expenses reasonably
incurred by an Indemnified Party in connection with investigating or defending
any such Claim; provided, however, that the indemnity agreement contained in
this Section 6(b) and the agreement with respect to contribution contained in
Section 7 shall not apply to amounts paid in settlement of any Claim if such
settlement is effected without the prior written consent of such Investor, which
consent shall not be unreasonably withheld or delayed; provided, further,
however, that the Investor shall be liable under this Section 6(b) for only that
amount of a Claim or Indemnified Damages as does not exceed the net proceeds to
such Investor as a result of the sale of Registrable Securities pursuant to such
Registration Statement. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of such Indemnified Party
and shall survive the transfer of the Registrable Securities by the Investors
pursuant to Section 9. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 6(b) with
respect to any preliminary prospectus shall not inure to the benefit of any
Indemnified Party if the untrue statement or omission of material fact contained
in the preliminary prospectus was corrected on a timely basis in the prospectus,
as then amended or supplemented.

            c. Promptly after an Indemnified Person or Indemnified Party under
this Section 6 has knowledge of any Claim as to which such Indemnified Person
reasonably believes indemnity may be sought or promptly after such Indemnified
Person or Indemnified Party receives notice of the commencement of any action or
proceeding (including any governmental action or proceeding) involving a Claim,
such Indemnified Person or Indemnified Party shall, if a Claim in respect
thereof is to be made against any indemnifying party under this Section 6,
deliver to the indemnifying party a written notice of such Claim, and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party

                                       12
<PAGE>

similarly noticed, to assume control of the defense thereof with counsel
selected by the indemnifying party and subject to the reasonable approval of the
Indemnified Person or the Indemnified Party, as the case may be; provided,
however, that an Indemnified Person or Indemnified Party shall have the right to
retain its own counsel with the fees and expenses of not more than one counsel
for such Indemnified Person or Indemnified Party to be paid by the indemnifying
party, if, in the reasonable opinion of counsel retained by the indemnifying
party, the representation by such counsel of the Indemnified Person or
Indemnified Party and the indemnifying party would be inappropriate due to
actual or potential differing interests between such Indemnified Person or
Indemnified Party and any other party represented by such counsel in such
proceeding. In the case of an Indemnified Person, legal counsel referred to in
the immediately preceding sentence shall be selected by the Investors holding at
least 60% in interest of the Registrable Securities included in the Registration
Statement to which the Claim relates. The Indemnified Party or Indemnified
Person shall cooperate fully with the indemnifying party in connection with any
negotiation or defense of any such action or Claim by the indemnifying party and
shall furnish to the indemnifying party all information reasonably available to
the Indemnified Party or Indemnified Person that relates to such action or
Claim. The indemnifying party shall keep the Indemnified Party or Indemnified
Person fully apprised at all times as to the status of the defense or any
settlement negotiations with respect thereto. No indemnifying party shall be
liable for any settlement of any action, claim or proceeding effected without
its prior written consent, provided, however, that the indemnifying party shall
not unreasonably withhold, delay or condition its consent. No indemnifying party
shall, without the prior written consent of the Indemnified Party or Indemnified
Person, consent to entry of any judgment or enter into any settlement or other
compromise that does not include as an unconditional term thereof the giving by
the claimant or plaintiff to such Indemnified Party or Indemnified Person of a
release from all liability in respect to such Claim or litigation. Following
indemnification as provided for hereunder, the indemnifying party shall be
subrogated to all rights of the Indemnified Party or Indemnified Person with
respect to all third parties, firms or corporations relating to the matter for
which indemnification has been made. The failure to deliver written notice to
the indemnifying party as provided herein shall not relieve such indemnifying
party of any liability to the Indemnified Person or Indemnified Party under this
Section 6, except to the extent that the indemnifying party is prejudiced in its
ability to defend such action.

            d. The indemnification required by this Section 6 shall be made by
periodic payments of the amount thereof during the course of the investigation
or defense, as and when bills are received or Indemnified Damages are incurred.

            e. The indemnity agreements contained herein shall be in addition to
(i) any cause of action or similar right of the Indemnified Party or Indemnified
Person against the indemnifying party or others, and (ii) any liabilities the
indemnifying party may be subject to pursuant to the law.

      7. Contribution.

      To the extent any indemnification by an indemnifying party is prohibited
or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to

                                       13
<PAGE>

any amounts for which it would otherwise be liable under Section 6 to the
fullest extent permitted by law; provided, however, that: (i) no contribution
shall be made under circumstances where the maker would not have been liable for
indemnification under the fault standards set forth in Section 6, (ii) no person
involved in the sale of Registrable Securities which person is guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933
Act) in connection with such sale shall be entitled to contribution from any
person involved in such sale of Registrable Securities who was not guilty of
fraudulent misrepresentation; and (iii) contribution by any seller of
Registrable Securities shall be limited in amount to the net amount of proceeds
received by such seller from the sale of such Registrable Securities pursuant to
such Registration Statement.

      8. Reports Under The 1934 Act.

      With a view to making available to the Investors the benefits of Rule 144
promulgated under the 1933 Act or any other similar rule or regulation of the
SEC that may at any time permit the Investors to sell securities of the Company
to the public without registration ("Rule 144"), the Company agrees to use its
best efforts to:

            a. make and keep public information available, as those terms are
understood and defined in Rule 144;

            b. file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements (it being understood that
nothing herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents is required for the applicable provisions of Rule 144; and

            c. furnish to each Investor so long as such Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company, if true, that it has complied with the applicable reporting
requirements of Rule 144, the 1933 Act and the 1934 Act, (ii) a copy of the most
recent annual or quarterly report of the Company and copies of such other
reports and documents so filed by the Company, and (iii) such other information
as may be reasonably requested to permit the Investors to sell such securities
pursuant to Rule 144 without registration.

      9. Assignment of Registration Rights.

      The rights under this Agreement shall be automatically assignable by the
Investors to any transferee of all or any portion of such Investor's Registrable
Securities if: (i) the Investor agrees in writing with the transferee or
assignee to assign such rights, and a copy of such agreement is furnished to the
Company within a reasonable time after such assignment; (ii) the Company is,
within a reasonable time after such transfer or assignment, furnished with
written notice of (a) the name and address of such transferee or assignee, and
(b) the securities with respect to which such registration rights are being
transferred or assigned; (iii) immediately following such transfer or assignment
the further disposition of such securities by the transferee or assignee is
restricted under the 1933 Act and applicable state securities laws; (iv) at or
before the time the Company receives the written notice contemplated by clause
(ii) of this sentence the

                                       14
<PAGE>

transferee or assignee agrees in writing with the Company to be bound by all of
the provisions contained herein; (v) such transfer shall have been made in
accordance with the applicable requirements of the Securities Purchase
Agreement, the Convertible Debentures and the Warrants; (vi) such transfer shall
have been conducted in accordance with all applicable federal and state
securities laws; and (vii) such transfer or assignment does not result in more
than ten (10) holders of Registrable Securities and, after giving effect to such
transfer or assignment, such assignee or transferee holds at least 10% of the
Registrable Securities (subject to appropriate adjustment for stock splits,
stock dividends, combinations, recapitalizations and other similar transactions)
or such lesser number if such transfer involves all of the Registrable
Securities then held by such transferor.

      10. Amendment of Registration Rights.

      Provisions of this Agreement may be amended and the observance thereof may
be waived (either generally or in a particular instance and either retroactively
or prospectively), only with the written consent of the Company and Investors
who then hold at least 60% of the Registrable Securities. Any amendment or
waiver effected in accordance with this Section 10 shall be binding upon each
Investor and the Company. No such amendment shall be effective to the extent
that it applies to less than all of the holders of the Registrable Securities.
No consideration shall be offered or paid to any Person to amend or consent to a
waiver or modification of any provision of any of this Agreement unless the same
consideration also is offered to all of the parties to this Agreement.

      11. Miscellaneous.

            a. A Person is deemed to be a holder of Registrable Securities
whenever such Person owns or is deemed to own of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more Persons with respect to the same Registrable
Securities, the Company shall act upon the basis of instructions, notice or
election received from such record owner of such Registrable Securities.

            b. Any notices, consents, waivers or other communications required
or permitted to be given under the terms of this Agreement must be in writing
and will be deemed to have been delivered: (i) upon receipt, when delivered
personally; (ii) upon receipt, when sent by facsimile (provided confirmation of
transmission is mechanically or electronically generated and kept on file by the
sending party); or (iii) one (1) Business Day after deposit with a nationally
recognized overnight delivery service, in each case properly addressed to the
party to receive the same. The addresses and facsimile numbers for such
communications shall be:

                                       15
<PAGE>

              If to the Company:

                       Hemispherx Biopharma, Inc.
                       One Penn Center
                       1617 JFK Boulevard, Suite 660
                       Philadelphia, PA  19103
                       Telephone:
                       Facsimile:
                       Attention: Chief Executive Officer

              With a copy to:

                       Ransom W. Etheridge, Esq.
                       2610 Potters Road
                       Suite 200
                       Virginia Beach, VA  23452
                       Telephone: 757-486-0599
                       Facsimile: 757-486-0792

              If to Legal Counsel:

                       Schulte Roth & Zabel LLP
                       919 Third Avenue
                       New York, New York 10022
                       Telephone: (212) 756-2000
                       Facsimile  (212) 593-5955
                       Attention: Eleazer Klein, Esq.

If to a Buyer, to its address and facsimile  number set forth on the Schedule of
Buyers attached hereto, with copies to such Buyer's representatives as set forth
on the Schedule of Buyers,  or to such other  address  and/or  facsimile  number
and/or  to the  attention  of such  other  person  as the  recipient  party  has
specified by written notice given to each other party five (5) days prior to the
effectiveness of such change.  Written  confirmation of receipt (A) given by the
recipient  of  such  notice,  consent,   waiver  or  other  communication,   (B)
mechanically  or  electronically  generated  by the sender's  facsimile  machine
containing the time, date,  recipient facsimile number and an image of the first
page of such  transmission  or (C)  provided by a courier or  overnight  courier
service shall be rebuttable  evidence of personal service,  receipt by facsimile
or receipt from a nationally recognized overnight delivery service in accordance
with clause (i), (ii) or (iii) above, respectively.

            c. Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

            d. All questions concerning the construction, validity, enforcement
and interpretation of this Agreement shall be governed by the internal laws of
the State of New York, without giving effect to any choice of law or conflict of
law provision or rule (whether of the State of New York or any other
jurisdictions) that would cause the application of the laws of any

                                       16
<PAGE>

jurisdictions other than the State of New York. Each party hereby irrevocably
submits to the non-exclusive jurisdiction of the state and federal courts
sitting in the City of New York, borough of Manhattan, for the adjudication of
any dispute hereunder or in connection herewith or with any transaction
contemplated hereby or discussed herein, and hereby irrevocably waives, and
agrees not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, that such suit, action
or proceeding is brought in an inconvenient forum or that the venue of such
suit, action or proceeding is improper. Each party hereby irrevocably waives
personal service of process and consents to process being served in any such
suit, action or proceeding by mailing a copy thereof to such party at the
address for such notices to it under this Agreement and agrees that such service
shall constitute good and sufficient service of process and notice thereof.
Nothing contained herein shall be deemed to limit in any way any right to serve
process in any manner permitted by law. If any provision of this Agreement shall
be invalid or unenforceable in any jurisdiction, such invalidity or
unenforceability shall not affect the validity or enforceability of the
remainder of this Agreement in that jurisdiction or the validity or
enforceability of any provision of this Agreement in any other jurisdiction.
EACH PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO
REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN
CONNECTION HEREWITH OR ARISING OUT OF THIS AGREEMENT OR ANY TRANSACTION
CONTEMPLATED HEREBY.

            e. This Agreement, the Securities Purchase Agreement, the Warrants,
the Convertible Debentures, the Security Agreement, and the documents referenced
herein and therein constitute the entire agreement among the parties hereto with
respect to the subject matter hereof and thereof. There are no restrictions,
promises, warranties or undertakings, other than those set forth or referred to
herein and therein. This Agreement, the Securities Purchase Agreement, the
Warrants, the Security Agreement, and the Convertible Debentures supersede all
prior agreements and understandings among the parties hereto with respect to the
subject matter hereof and thereof.

            f. Subject to the requirements of Section 9, this Agreement shall
inure to the benefit of and be binding upon the permitted successors and assigns
of each of the parties hereto.

            g. The headings in this Agreement are for convenience of reference
only and shall not limit or otherwise affect the meaning hereof.

            h. This Agreement may be executed in identical counterparts, each of
which shall be deemed an original but all of which shall constitute one and the
same agreement. This Agreement, once executed by a party, may be delivered to
the other parties hereto by facsimile transmission of a copy of this Agreement
bearing the signature of the party so delivering this Agreement.

            i. Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to

                                       17
<PAGE>

carry out the intent and accomplish the purposes of this Agreement and the
consummation of the transactions contemplated hereby.

            j. All consents and other determinations required to be made by the
Investors pursuant to this Agreement shall be made, unless otherwise specified
in this Agreement, by Investors holding at least 60% of the Registrable
Securities, determined as if all of the Convertible Debentures held by Investors
then outstanding have been converted into Registrable Securities and all
Warrants then outstanding have been exercised for Registrable Securities without
regard to any limitations on conversion of the Convertible Debentures or on
exercise of the Warrants.

            k. The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent and no rules of
strict construction will be applied against any party.

            l. This Agreement is intended for the benefit of the parties hereto
and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other Person.

                                   * * * * * *

                                       18
<PAGE>

            IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of day and year first above written.

COMPANY:

HEMISPHERX BIOPHARMA, INC.

By:
    -------------------------------------
    Name:
    Its:

                    [Signatures of Buyers on Following Page]

                                       19
<PAGE>

                [SIGNATURE PAGE TO REGISTRATION RIGHTS AGREEMENT]

                                BUYERS:

                                PORTSIDE GROWTH & OPPORTUNITY FUND

                                By:
                                           -----------------------------------
                                Name:
                                           -----------------------------------
                                Title:
                                           -----------------------------------

                                LEONARDO, L.P.

                                By:
                                           -----------------------------------
                                Name:
                                           -----------------------------------
                                Title:
                                           -----------------------------------

                                       20
<PAGE>

                               SCHEDULE OF BUYERS

<TABLE>
<CAPTION>
                                                                     Investor's Representative's
                                        Investor Address                       Address
    Investor                          and Facsimile Number              and Facsimile Number
    --------                          --------------------              --------------------
<S>                        <C>                                  <C>
Portside Growth &          c/o Ramius Capital Group, LLC        Schulte Roth & Zabel LLP
Opportunity Fund           666 Third Avenue, 26th Floor         919 Third Avenue
                           New York, NY 10017                   New York, NY 10022
                           Attention:  Jeffrey Smith            Attn:  Eleazer Klein
                                      Andrew Strober            Telephone:  212-756-2000
                           Telephone: (212) 845-7955            Facsimile: (212) 593-5955
                           Facsimile: (212) 845-7999

                                                                Paul, Weiss, Rifkind, Wharton &
Leonardo, L.P.             c/o Angelo Gordon, LP                Garrison LLP
                           245 Park Avenue                      1285 Avenue of the Americas
                           New York, NY 10167                   New York, NY 10019
                           Attention:  Fred Berger              Attention:  Jaideep P. Reddy, Esq.
                                             Gary Wolf          Telephone: (212) 373-3000
                           Telephone:  (212) 867-6449           Facsimile: (212) 757-3990
                           Facsimile:  (212) 867-6449
</TABLE>

<PAGE>

                                                                       EXHIBIT A

                         FORM OF NOTICE OF EFFECTIVENESS
                            OF REGISTRATION STATEMENT

[Transfer Agent]
[Address]

      Re: Hemispherx Biopharma, Inc.

Ladies and Gentlemen:

      We are counsel to Hemispherx Biopharma, Inc.., a Delaware corporation (the
"Company"), and have represented the Company in connection with that certain
Securities Purchase Agreement (the "Purchase Agreement") entered into by and
among the Company and the buyers named therein (collectively, the "Holders")
pursuant to which the Company issued to the Holders its 6% Senior Secured
Debentures, (the "Convertible Debentures") convertible into shares of the
Company's Common Stock, par value $0.001 per share (the "Common Stock") and
warrants exercisable for shares of its Common Stock (the "Warrants"). Pursuant
to the Purchase Agreement, the Company also has entered into a Registration
Rights Agreement with the Holders (the "Registration Rights Agreement") pursuant
to which the Company agreed, among other things, to register the Registrable
Securities (as defined in the Registration Rights Agreement), including the
shares of Common Stock issuable upon conversion of the Convertible Debentures
and exercise of the Warrants under the Securities Act of 1933, as amended (the
"1933 Act"). In connection with the Company's obligations under the Registration
Rights Agreement, on ____________ ___, 2003, the Company filed a Registration
Statement on Form S-3 (File No. 333-_____________) (the "Registration
Statement") with the Securities and Exchange Commission (the "SEC") relating to
the Registrable Securities, which names each of the Holders as a selling
stockholder thereunder.

      In connection with the foregoing, we advise you that a member of the SEC's
staff has advised us by telephone that the SEC has entered an order declaring
the Registration Statement effective under the 1933 Act at [ENTER TIME OF
EFFECTIVENESS] on [ENTER DATE OF EFFECTIVENESS] and we have no knowledge, after
telephonic inquiry of a member of the SEC's staff, that any stop order
suspending its effectiveness has been issued or that any proceedings for that
purpose are pending before, or threatened by, the SEC and the Registrable
Securities are available for resale under the 1933 Act pursuant to the
Registration Statement.

                                    Very truly yours,

                                    [ISSUER'S COUNSEL]

                                    By:
                                        ---------------------------

CC: [LIST NAMES OF HOLDERS]<PAGE>
                                                                     Exhibit 4.3

================================================================================

                                  INTEVAC, INC.

                                       AND
                              ---------------------

           STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A.

                                   AS TRUSTEE

                6-1/2% CONVERTIBLE SUBORDINATED NOTES DUE 2009

                              ---------------------
                                    INDENTURE

                            DATED AS OF JULY 12, 2002

================================================================================
<PAGE>
                                TABLE OF CONTENTS
                                                                           PAGE

ARTICLE I Definitions and Incorporation by Reference.........................1

      SECTION 1.01   Definitions.............................................1

      SECTION 1.02   Other Definitions.......................................7

      SECTION 1.03   Incorporation by Reference of Trust Indenture Act.......8

      SECTION 1.04   Rules of Construction...................................8

ARTICLE II The Securities....................................................9

      SECTION 2.01   Form and Dating.........................................9

      SECTION 2.02   Execution and Authentication...........................10

      SECTION 2.03   Registrar, Paying Agent and Conversion Agent...........10

      SECTION 2.04   Paying Agent to Hold Money in Trust....................11

      SECTION 2.05   Securityholder.........................................11

      SECTION 2.06   Transfer and Exchange..................................11

      SECTION 2.07   Replacement Securities.................................12

      SECTION 2.08   Outstanding Securities.................................12

      SECTION 2.09   Treasury Securities....................................12

      SECTION 2.10   Temporary Securities: Exchange of Global Security

                     for Certificated Securities............................13

      SECTION 2.11   Cancellation...........................................13

      SECTION 2.12   Defaulted Interest.....................................14

ARTICLE III Redemption......................................................14

      SECTION 3.01   Notices to Trustee.....................................14

      SECTION 3.02   Selection of Securities to be Redeemed.................14

      SECTION 3.03   Notice of Redemption...................................14

      SECTION 3.04   Effect of Notice of Redemption.........................15

      SECTION 3.05   Deposit of Redemption Price............................15

      SECTION 3.06   Securities Redeemed in Part............................15

      SECTION 3.07   Optional Redemption....................................16

      SECTION 3.08   Designated Event Offer.................................16

      SECTION 3.09   Conversion Arrangement on Underwritten Call for

                     Redemption.............................................18

ARTICLE IV Covenants........................................................18

      SECTION 4.01   Payment of Securities..................................18

      SECTION 4.02   SEC Reports............................................19

      SECTION 4.03   Compliance Certificate.................................19

      SECTION 4.04   Stay, Extension and Usury Law..........................19

      SECTION 4.05   Corporate Existence....................................20

      SECTION 4.06   Maintenance of Properties..............................20

      SECTION 4.07   Payment of Taxes and Other Claims......................20

                                      i
<PAGE>
                                TABLE OF CONTENTS
                                   (Continued)

      SECTION 4.08   Designated Event.......................................20

      SECTION 4.09   Triggering Distribution................................21

      SECTION 4.10   Further Instruments and Acts...........................21

ARTICLE V Conversion........................................................21

      SECTION 5.01   Conversion Privilege...................................21

      SECTION 5.02   Conversion Procedure...................................22

      SECTION 5.03   Fractional Shares......................................22

      SECTION 5.04   Taxes on Conversion....................................22

      SECTION 5.05   Company to Provide Stock...............................23

      SECTION 5.06   Adjustment of Conversion Price.........................23

      SECTION 5.07   No Adjustment..........................................26

      SECTION 5.08   Other Adjustments......................................26

      SECTION 5.09   Adjustments for Tax Purposes...........................27

      SECTION 5.10   Adjustments by the Company.............................27

      SECTION 5.11   Notice of Adjustment...................................27

      SECTION 5.12   Notice of Certain Transactions.........................27

      SECTION 5.13   Effect of Reclassifications, Consolidations,

                     Mergers or Sales on Conversion Privilege...............27

      SECTION 5.14   Trustee's Disclaimer...................................28

      SECTION 5.15   Automatic Conversion...................................29

ARTICLE VI Subordination....................................................30

      SECTION 6.01   Agreement to Subordinate...............................30

      SECTION 6.02   No Payment on Securities if Senior Debt in Default.....30

      SECTION 6.03   Distribution on Acceleration of Securities;

                     Dissolution and Reorganization: Subrogation of

                     Securities.............................................31

      SECTION 6.04   Reliance by Holders of Senior Debt on

                     Subordination Provisions...............................34

      SECTION 6.05   No Waiver of Subordination Provisions..................34

      SECTION 6.06   Trustee's Relation to Senior Debt......................35

  SECTION 6.07   Other Provisions Subject Hereto..........................  35

      SECTION 6.08   Certain Conversions and Repurchases Deemed Payment.....35

ARTICLE VII Successors......................................................36

      SECTION 7.01   Merger, Consolidation or Sale of Assets................36

      SECTION 7.02   Successor Corporate Entity Substituted.................36

ARTICLE VIII Defaults and Remedies..........................................37

      SECTION 8.01   Events of Default......................................37

      SECTION 8.02   Acceleration...........................................38

      SECTION 8.03   Other Remedies.........................................38

                                       ii
<PAGE>
                                TABLE OF CONTENTS
                                   (Continued)

      SECTION 8.04   Waiver of Past Defaults................................39

      SECTION 8.05   Control by Majority....................................39

      SECTION 8.06   Limitation on Suits....................................39

      SECTION 8.07   Rights of Securityholders to Receive Payment...........39

      SECTION 8.08   Collection Suit by Trustee.............................40

      SECTION 8.09   Trustee May File Proofs of Claim.......................40

      SECTION 8.10   Priorities.............................................40

      SECTION 8.11   Undertaking for Costs..................................40

ARTICLE IX Trustee..........................................................40

      SECTION 9.01   Duties of Trustee......................................41

      SECTION 9.02   Rights of Trustee......................................41

      SECTION 9.03   Individual Rights of Trustee...........................42

      SECTION 9.04   Trustee's Disclaimer...................................42

      SECTION 9.05   Notice of Defaults.....................................42

      SECTION 9.06   Reports by Trustee to Securityholders..................42

      SECTION 9.07   Compensation and Indemnity.............................42

      SECTION 9.08   Replacement of Trustee.................................43

      SECTION 9.09   Successor Trustee by Merger, Etc.......................44

      SECTION 9.10   Eligibility; Disqualification..........................44

      SECTION 9.11   Preferential Collection of Claims Against Company......44

      SECTION 9.12   Sections Applicable to Registrar, Paying Agent and

                     Conversion Agent.......................................44

ARTICLE X Discharge of Indenture............................................45

      SECTION 10.01  Termination of Company's Obligation....................45

      SECTION 10.02  Repayment to Company...................................45

ARTICLE XI Amendments, Supplements and Waivers..............................45

      SECTION 11.01  Without Consent of Securityholders.....................45

      SECTION 11.02  With Consent of Securityholders........................46

      SECTION 11.03  Compliance with Trust Indenture Act....................47

      SECTION 11.04  Revocation and Effect of Consents......................47

      SECTION 11.05  Notation on or Exchange of Securities..................48

      SECTION 11.06  Trustee Protected......................................48

ARTICLE XII Miscellaneous...................................................48

      SECTION 12.01  Trust Indenture Act Controls...........................48

      SECTION 12.02  Notices................................................48

      SECTION 12.03  Communication by Securityholders with Other

                     Securityholders........................................49

      SECTION 12.04  Certificate and Opinion as to Conditions Precedent.....49

                                       iii
<PAGE>
                               TABLE OF CONTENTS
                                  (Continued)

      SECTION 12.05  Statements Required in Certificate or Opinion..........49

      SECTION 12.06  Rules by Trustee and Agents............................49

      SECTION 12.07  Legal Holidays.........................................49

      SECTION 12.08  No Recourse Against Others.............................50

      SECTION 12.09  Counterparts...........................................50

      SECTION 12.10  Variable Provisions....................................50

      SECTION 12.11  Governing Law..........................................51

      SECTION 12.12  No Adverse Interpretation of Other Agreements..........51

      SECTION 12.13  Successors.............................................51

      SECTION 12.14  Severability...........................................51

      SECTION 12.15  Table of Contents, Headings, Etc.......................51

ARTICLE XIII Repurchase Offer...............................................51

      SECTION 13.01  Repurchase Offer.......................................51

      SECTION 13.02  Repurchase Notice......................................52

      SECTION 13.03  Deposit of Repurchase Offer Amount.....................53

      SECTION 13.04  Compliance with Applicable Laws........................53

EXHIBIT A     FORM OF CONVERTIBLE SUBORDINATED NOTE........................A-1

                                       iv
<PAGE>
      INDENTURE dated as of July 12, 2002 between Intevac, Inc., a California
corporation (the "Company") and State Street Bank and Trust Company of
California, N.A., a national banking association under the laws of the United
States of America, as Trustee (the "Trustee").

      Each party agrees as follows for the benefit of the other party and for
the equal and ratable benefit of the Securityholders of the Company's 6-1/2%
Convertible Subordinated Notes due 2009 (the "Securities"):

                                   ARTICLE I

                   Definitions and Incorporation by Reference

SECTION 1.01 Definitions

      "Affiliate" of any specified person means any other person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified person. For the purposes of this definition,
"control" (including, with correlative meanings, the terms "controlling",
"controlled by" and "under common control with"), as used with respect to any
person, shall mean the possession, directly or indirectly, of the power to
direct or cause the direction of the management or policies of such person,
whether through the ownership of voting securities or by agreement or otherwise.

      "Agent" means any Registrar, Paying Agent, Conversion Agent or
co-registrar.

      "Board of Directors" means the Board of Directors of the Company or any
authorized committee of the Board.

      "Board Resolution" means a copy of a resolution of the Board of Directors
certified by the Secretary or an Assistant Secretary of the Company to be in
full force and effect on the date of such certification and delivery to the
Trustee.

      "Business Day" means any day that is not a Legal Holiday.

      "Capital Stock" means with respect to any entity any and all shares,
interests, participations, rights or other equivalents (however designated) of
equity interests in entity, including, without limitation, corporate stock and
partnership interests.

      "Change of Control" means any event where: (i) any "person" or "group" (as
such terms are used in Section 13(d) and 14(d) of the Exchange Act) is or
becomes the "beneficial owner" (as defined in Rules 13d-3 and 13d-5 under the
Exchange Act) of shares representing more than 50% of the combined voting power
of the then-outstanding securities entitled to vote generally in elections of
directors of the Company ("Voting Stock"), (ii) the Company consolidates with or
merges into any other corporation, or any other corporation merges into the
Company, and, in the case of any such transaction, the outstanding Common Stock
of the Company is reclassified into or exchanged
<PAGE>
for any other property or security, unless the shareholders of the Company
immediately before such transaction own, directly or indirectly immediately
following such transaction, at least a majority of the combined voting power of
the outstanding voting securities of the Corporate Entity resulting from such
transaction in substantially the same proportion as their ownership of the
Voting Stock immediately before such transaction, (iii) the Company conveys,
transfers or leases all or substantially all of its assets to any person, unless
such conveyance, transfer or lease is to a corporation and the shareholders of
the Company immediately before such conveyance, transfer or lease own, directly
or indirectly immediately following such transaction, at least a majority of the
combined voting power of the Corporate Entity to which such assets are so
conveyed, transferred or leased in the same proportion as their ownership of the
Voting Stock immediately before such transaction, or (iv) any time the
Continuing Directors do not constitute a majority of the Board of Directors of
the Company (or, if applicable, a successor corporation to the Company);
provided, that a Change of Control shall not be deemed to have occurred if at
least 90% of the consideration (excluding cash payments for fractional shares)
in the transaction or transactions constituting the Change of Control consists
of shares of common stock that are, or upon issuance will be, traded on a United
States national securities exchange or approved for trading on an established
automated over-the-counter trading market in the United States.

      "Common Stock" means the common stock of the Company as the same exists at
the date of the execution of this Indenture or as such stock may be constituted
from time to time.

      "Company" means the party named as such above until a successor replaces
it in accordance with Article VI and thereafter means the successor.

      "Continuing Directors" means, as of any date of determination, any member
of the Board of Directors of the Company who (i) was a member of such Board of
Directors on the date of this Indenture or (ii) was nominated for election or
elected to such Board of Directors with the approval of a majority of the
Continuing Directors who were members of such board at the time of such
nomination or election.

      "Corporate Entity" shall be any corporation, limited liability company or
other business entity.

      "Custodian" means State Street Bank and Trust Company of California, N.A.,
as custodian with respect to the Global Securities, or any successor entity
thereto.

      "Daily Market Price" means the price of a share of Common Stock on the
relevant date, determined (a) on the basis of the last reported sale price
regular way of the Common Stock as reported on the NNM, or if the Common Stock
is not then listed on the NNM, as reported on such national securities exchange
upon which the Common Stock is listed, or (b) if there is no such reported sale
on the day in question, on the basis of the average of the closing bid and asked
quotations regular way as so reported, or (c) if the Common Stock is not listed
on the NNM or on any national securities exchange, on the basis of the average
of the high bid and low asked quotations regular way on the day in question in
the over-the-counter market as reported by the

                                       -2-
<PAGE>
National Association of Securities Dealers Automated Quotation System, or if not
so quoted, as reported by National Quotation Bureau, Incorporated, or a similar
organization.

      "Default" means any event that is, or with the passage of time or the
giving of notice or both, would be an Event of Default. "Depositary" means The
Depository Trust Company, its nominees and their respective successors.

      "Designated Event" means the occurrence of a Change of Control or a
Termination of Trading.

      "Designated Senior Debt" means any Senior Debt which, at the date of
determination, has an aggregate principal amount outstanding of, or commitments
to lend up to, at least $10.0 million and is specifically designated by the
Company in the instrument evidencing or governing such Senior Debt as
"Designated Senior Debt" for purposes of this Indenture (provided, that such
instrument may place limitations and conditions on the right of such Senior Debt
to exercise the rights of Designated Senior Debt).

      "Exchange Act" means the Securities Exchange Act of 1934, as amended.

      "Excess Payment" means the excess of (A) the aggregate of the cash and
fair market value of other consideration paid by the Company or any of its
Subsidiaries with respect to the shares acquired in a tender offer or other
negotiated transaction over (B) the Daily Market Price on the Trading Day
immediately following the completion of such tender offer or other negotiated
transaction multiplied by the number of acquired shares.

      "GAAP" means generally accepted accounting principles set forth in the
opinions and pronouncements of the Accounting Principles Board of the American
Institute of Certified Public Accountants and statements and pronouncements of
the Financial Accounting Standards Board or in such other statements by such
other entity as may be approved by a significant segment of the accounting
profession in the United States, which are in effect from time to time.

      "Guarantee" means a guarantee (other than by endorsement of negotiable
instruments for collection in the ordinary course of business), direct or
indirect, in any manner (including, without limitation, letters of credit and
reimbursement agreements in respect thereof), of all or any part of any
Indebtedness.

      "Indebtedness" means, with respect to any person, all obligations, whether
or not contingent, of such person (i)(a) for borrowed money (including, but not
limited to, any indebtedness secured by a security interest, mortgage or other
lien on the assets of such person which is (1) given to secure all or part of
the purchase price of property subject thereto, whether given to the vendor of
such property or to another, or (2) existing on property at the time of
acquisition thereof), (b) evidenced by a note, debenture, bond or other written
instrument, (c) under a lease required to be capitalized on the balance sheet of
the lessee under GAAP or under any lease or related document (including a

                                       -3-
<PAGE>
purchase agreement) which provides that such person is contractually obligated
to purchase or to cause a third party to purchase such leased property, (d) in
respect of letters of credit, loan, bank guarantees or bankers' acceptances, (e)
with respect to Indebtedness secured by a mortgage, pledge, lien, encumbrance,
charge or adverse claim affecting title or resulting in an encumbrance to which
the property or assets of such person are subject, whether or not the obligation
secured thereby shall have been assumed or guaranteed by or shall otherwise be
such person's legal liability, (f) in respect of the balance of the deferred and
unpaid purchase price of any property or assets, (g) under interest rate,
currency or credit swap agreements, cap, floor and collar agreements, spot and
forward-contracts and similar agreements and arrangements; (ii) with respect to
any obligation of others of the type described in the preceding clause (i) or
under clause (iii) below assumed by or guaranteed in any manner by such person
or in effect guaranteed by such person through an agreement to purchase
(including, without limitation, "take or pay" and similar arrangements),
contingent or otherwise (and the obligations of such person under any such
assumptions, guarantees or other such arrangements); and (iii) any and all
deferrals, renewals, extensions, refinancings and refundings of, or amendments,
modifications or supplements to, any of the foregoing.

      "Indenture" means this Indenture as amended from time to time.

      "Issuance Date" means the date on which the Securities are first
authenticated and issued.

      "Material Subsidiary" means any Subsidiary of the Company which at the
date of determination is a "significant subsidiary" as defined in Rule 1-02(w)
of Regulation S-X under the Securities Act and the Exchange Act (as such
Regulation is in effect on the date hereof).

      "NNM" means the Nasdaq Stock Market's National Market.

      "Obligations" means any principal, interest, penalties, fees,
indemnifications, reimbursements, damages and other liabilities payable under
the documentation governing any Indebtedness.

      "Offering Circular" means the Offering Circular relating to the Securities
dated June 21, 2002, as supplemented on July 3, 2002, and as the same may be
amended or further supplemented from time to time.

      "Officers' Certificate" means a certificate signed by two Officers, one of
whom must be the Chairman of the Board, the President, the Chief Financial
Officer, the Treasurer or a Vice-President of the Company. See Sections 12.04
and 12.05 hereof.

      "Opinion of Counsel" means a written opinion from legal counsel who is
acceptable to the Trustee. The counsel may be an employee of or counsel to the
Company or the Trustee. See Sections 12.04 and 12.05 hereof.

      "person" means any individual, corporation, partnership, joint venture,
association, joint stock company, trust, unincorporated organization or
government or any agency or political subdivision thereof.

                                       -4-
<PAGE>
      "Photonics Business" means the design, development, manufacture and
service of the Photonic Products by the Company or one of its Subsidiaries.

      "Photonics Products" means:

        (i) the Company's Electron Bombarded Charge Coupled Device ("EBCCD")
            that is a sensor that has a transparent glass window on one side
            through which photons are focused onto a photocathode grown on the
            vacuum side of the window, such that when these photons strike the
            photocathode through the window, electrons are emitted into the
            vacuum and these electrons are then electrically accelerated through
            the vacuum and strike a charge coupled device ("CCD") imager, which
            in turn outputs a high resolution, low noise video signal;

       (ii) the Company's Electron Bombarded Active Pixel Sensor ("EBAPS") that
            incorporates the same basic technology as described in clause (i)
            above but contains a Complementary Metal-Oxide-Semiconductor
            ("CMOS") imager instead of a CCD chip;

      (iii) the Company's Laser Illuminated Viewing and Ranging system ("LIVAR")
            that is an EBCCD sensor with a laser illuminator that operates in a
            manner similar to RADAR, but utilizing an eye safe laser, rather
            than a longer wavelength microwave source, and displaying the
            reflected signal as a digital video image, rather than as a blip;
            and

       (iv) any products derived from the devices specified in (i) through (iii)
            above.

      "principal" of a debt security means the principal of the security plus
the premium, if any, on the security.

      "Representative" means the trustee, agent or representative (if any) for
an issue of Senior Debt.

      "SEC" means the Securities and Exchange Commission.

      "Securities" means the Securities described in the preamble above that are
issued, authenticated and delivered under this Indenture.

      "Securities Act" means the Securities Act of 1933, as amended.

      "Securityholder" or "holder" means a person in whose name a Security is
registered.

      "Senior Debt" means the principal of, premium, if any, interest, on, and
fees, costs and expenses in connection with, and other amounts due on
Indebtedness of the Company, whether

                                       -5-
<PAGE>

outstanding on the date of the Indenture or thereafter created, incurred,
assumed or guaranteed by the Company, unless, in the instrument creating or
evidencing or pursuant to which Indebtedness is outstanding, it is expressly
provided that such Indebtedness is not senior in right of payment to the
Securities. Senior Debt includes, with respect to the obligations described
above, interest accruing, pursuant to the terms of such Senior Debt, on or after
the filing of any petition in bankruptcy or for reorganization relating to the
Company, whether or not post-filing interest is allowed in such proceeding, at
the rate specified in the instrument governing the relevant obligation.
Notwithstanding anything to the contrary in the foregoing, Senior Debt shall not
include: (a) Indebtedness of the Company to a Subsidiary of the Company; (b) the
Securities; (c) the Company's 6-1/2% Convertible Subordinated Notes due 2004;
(d) Indebtedness of or amount owned by the Company for compensation to
employees, or for goods, services or material purchased in the ordinary course
of business; or (e) any liability for federal, state, local or other taxes owed
or owing by the Company. For the purposes of this definition of Senior Debt
under this Indenture, it is the intent of the parties hereto that the Securities
issued under this Indenture be "Senior Debt" (as defined under that certain
Indenture, dated February 15, 1997, between the Company and State Street Bank
and Trust Company of California, N.A. (the "2004 Indenture")) for purposes of
the 6-1/2% Convertible Subordinated Notes due 2004 (the "Existing Notes") issued
under the 2004 Indenture, and in furtherance thereof, the parties hereto agree
that nothing contained in this Indenture or in the definition of Senior Debt
under this Indenture is meant to or shall be construed to expressly provide that
the Securities issued under this Indenture are not superior to the Existing
Notes.

      "Subsidiary" means any corporation, association or other business entity
of which more than 50% of the total voting power of shares of Capital Stock
entitled (without regard to the occurrence of any contingency) to vote in the
election of directors, managers or trustees thereof is at the time owned or
controlled, directly or indirectly, by any person or one or more of the other
Subsidiaries of that person or a combination thereof.

      "Termination of Trading" will be deemed to have occurred if the Common
Stock (or other common stock into which the Securities are then convertible) is
neither listed for trading on a United States national securities exchange nor
approved for trading on an established automated over-the-counter trading market
in the United States.

      "TIA" means the Trust Indenture Act of 1939, and rules and regulations
thereunder as so amended as in effect on the date of execution of this
Indenture; provided, however, in the event that Trust Indenture Act of 1939 is
amended after such date, "Trust Indenture Act" means, to the extent required by
any such amendment, the Trust Indenture Act of 1939 as so amended.

      "Trading Day" shall mean (A) if the applicable security is quoted on the
NNM, a day on which trades may be made thereon, (B) if the applicable security
is listed or admitted for trading on the New York Stock Exchange or another
national securities exchange, a day on which the New York Stock Exchange or such
other national securities exchange is open for business or (C) if the applicable
security is not so listed, admitted for trading or quoted, any day other than a
Saturday or Sunday or a day on which banking institutions in the State of New
York or the State of California are authorized or obligated by law or executive
order to close.

                                      -6-
<PAGE>
      "Triggering Distribution" means an event where the Company declares or
makes any dividend or other distribution to all of the holders of the Common
Stock of shares of Capital Stock of any Subsidiary that at the time constitutes
the Company's Photonics Business.

      "Trustee" means the party named as such above until a successor replaces
it in accordance with the applicable provisions of this Indenture and thereafter
means the successor.

      "Trust Officer" means any officer or assistant officer of the Trustee
assigned by the Trustee to administer this Indenture.

      SECTION 1.02 Other Definitions.

<TABLE>
<CAPTION>
                                                                      Defined in
                                                                    Term Section
<S>                                                                     <C>
"Agent Members"...................................................      2.01

"Automatic Conversion"............................................      15.15

"Automatic Conversion Notice".....................................      15.15

"Bankruptcy Custodian"............................................      8.01

"Bankruptcy Law"..................................................      8.01

"Designated Event Offer"..........................................      4.08

"Designated Event Payment"........................................      4.08

"Designated Event Payment Date"...................................      3.08

"Commencement Date"...............................................      3.08

"Conversion Agent"................................................      2.03

"Conversion Date".................................................      5.02

"Conversion Price"................................................      5.01

"Current Market Price"............................................      5.06(e)

"Event of Default"................................................      8.01

"Global Security".................................................      2.01

"Legal Holiday"...................................................      12.07

"Offer Amount"....................................................      3.08

"Officer".........................................................      12.10

"Paying Agent"....................................................      2.03

"Payment Blockage Notice".........................................      6.02

"Payment Blockage Period".........................................      6.02

"Payment Default".................................................      8.01
</TABLE>

                                      -7-
<PAGE>
<TABLE>
<CAPTION>
                                                                      Defined in
                                                                    Term Section
<S>                                                                     <C>
"Purchase Agreement"..............................................      2.01

"Purchase Date"...................................................      5.06

"Registrar".......................................................      2.03

"Repurchase Commencement Date"....................................      13.01

"Repurchase Offer"................................................      4.09

"Repurchase Offer Agreement"......................................      13.01

"Repurchase Payment"..............................................      4.09

"Repurchase Payment Date".........................................      4.09

"Restricted Securities"...........................................      2.01

"Tender Period"...................................................      3.08
</TABLE>

      SECTION 1.03 Incorporation by Reference of Trust Indenture Act. Whenever
this Indenture refers to a provision of the TIA, the provision is incorporated
by reference in and made a part of this Indenture.

      The following TIA terms used in this Indenture have the following
meanings:

      "indenture securities" means the Securities;

      "indenture security holder" means a Securityholder;

      "indenture to be qualified" means this Indenture;

      "indenture trustee" or "institutional trustee" means the Trustee; and

      "obligor" on the Securities means the Company or any other obligor on
the Securities.

      All other terms used in this Indenture that are defined by the TIA,
defined by TIA reference to another statute or defined by SEC rule under the TIA
have the meanings so assigned to them.

      SECTION 1.04 Rules of Construction. Unless the context otherwise requires:

            (a) a term has the meaning assigned to it;

            (b) an accounting term not otherwise defined has the meaning
assigned to it in accordance with GAAP consistently applied;

            (c) "or" is not exclusive;

                                      -8-
<PAGE>
            (d) words in the singular include the plural, and words in the
plural include the singular; and

            (e) provisions apply to successive events and transactions.

                                   ARTICLE II

                                 The Securities

      SECTION 2.01 Form and Dating. The Securities and the Trustee's certificate
of authentication shall be substantially in the form of Exhibit A which is
hereby incorporated in and expressly made a part of this Indenture.

      The Securities may have notations, legends or endorsements required by
law, stock exchange rule, agreements to which the Company is subject, if any, or
usage (provided that any such notation, legend or endorsement is in a form
acceptable to the Company). The Company shall furnish any such legend not
contained in Exhibit A to the Trustee in writing. The Securities shall be dated
the date of their authentication. The terms and provisions of the Securities set
forth in Exhibit A are part of the terms of this Indenture and to the extent
applicable, the Company and the Trustee, by their execution and delivery of this
Indenture, expressly agree to such terms and provisions and to be bound thereby.

            (a) Global Securities. The Securities shall be issued in the form of
one or more global Securities in definitive, fully registered form without
interest coupons with the global securities legend set forth in Exhibit A hereto
(a "Global Security"). The Global Securities shall be deposited on behalf of the
purchasers of the Securities represented thereby with the Trustee as Custodian
for the Depositary, and registered in the name of the Depositary or a nominee of
the Depositary, duly executed by the Company and authenticated by the Trustee as
hereinafter provided. The aggregate principal amount of the Global Security may
from time to time be increased or decreased by adjustments made on the records
of the Trustee and the Depositary or its nominee as hereinafter provided in this
Article II.

            (b) Book-Entry Provisions. This Section 2.01(b) shall apply only to
a Global Security deposited with or on behalf of the Depositary.

      The Company shall execute and the Trustee shall, in accordance with this
Section 2.01(b) and the written order of the Company, authenticate and deliver
initially one or more Global Securities that (i) shall be registered in the name
of Cede & Co. or other nominee of such Depositary and (ii) shall be delivered by
the Trustee to such Depositary or pursuant to such Depositary's instructions or
held by the Trustee as Custodian for the Depositary pursuant to a FAST Balance
Certificate Agreement between the Depositary and the Trustee.

      Members of, or participants in, the Depositary ("Agent Members") shall
have no rights under this Indenture with respect to any Global Security held on
their behalf by the Depositary or by the Trustee as the Custodian for the
Depositary or under such Global Security, and the Depositary or its

                                      -9-
<PAGE>
nominee, as the case may be, may be treated by the Company, the Trustee and any
agent of the Company or the Trustee as the absolute owner of such Global
Security for all purposes whatsoever. Notwithstanding the foregoing, nothing
herein shall prevent the Company, the Trustee or any agent of the Company or the
Trustee from giving effect to any written certification, proxy or other
authorization furnished by the Depositary or impair, as between the Depositary
and its Agent Members, the operation of customary practices of such Depositary
governing the exercise of the rights of a holder of a beneficial interest in any
Global Security.

      SECTION 2.02 Execution and Authentication. Two Officers shall sign the
Securities for the Company by manual or facsimile signature.

      If an Officer whose signature is on a Security no longer holds that office
at the time the Security is authenticated, the Security shall nevertheless be
valid.

      A Security shall not be valid until authenticated by the manual signature
of an authorized officer of the Trustee. The signature shall be conclusive
evidence that the Security has been authenticated under this Indenture.

      Upon a written order of the Company signed by two Officers, the Trustee
shall authenticate the Securities for original issue up to an aggregate
principal amount of $29,543,000. The aggregate principal amount of Securities
outstanding at any time shall not exceed such aggregate amount of $29,543,000
except as provided in Section 2.07.

      The Trustee may appoint an authenticating agent acceptable to the Company
to authenticate Securities. An authenticating agent may authenticate Securities
whenever the Trustee may do so. Each reference in this Indenture to
authentication by the Trustee includes authentication by such agent. An
authenticating agent has the same rights as an Agent to deal with the Company or
an Affiliate.

      SECTION 2.03 Registrar, Paying Agent and Conversion Agent. The Company
shall maintain in the Borough of Manhattan, City of New York, State of New York
(i) an office or agency where Securities may be presented for registration of
transfer or for exchange ("Registrar"), (ii) an office or agency where
Securities may be presented for payment ("Paying Agent") and (iii) an office or
agency where Securities may be presented for conversion ("Conversion Agent").
The Registrar shall keep a register of the Securities and of their transfer and
exchange. The Company may appoint the Registrar, the Paying Agent and the
Conversion Agent. The Company may appoint one or more co-registrars, one or more
additional paying agents and one or more additional conversion agents in such
other locations as it shall determine; provided that no such designation shall
in any manner relieve the Company of its obligation to maintain an office or
agency in the Borough of Manhattan, The City of New York, State of New York, for
such purposes. The term "Paying Agent" includes any additional paying agent and
the term "Conversion Agent" includes any additional conversion agent. The
Company may change any Paying Agent, Registrar, co-registrar or Conversion Agent
without prior notice to any Securityholder. The Company shall notify the Trustee
of the name and address of any Agent not a party to this Indenture. If the
Company fails to appoint or maintain another entity as Registrar, Paying Agent
or Conversion Agent, the Trustee shall act as such. The

                                      -10-
<PAGE>
Company or any of its Affiliates may act as Paying Agent, Registrar,
co-registrar or Conversion Agent. The Company initially appoints the Trustee as
Paying Agent, Registrar, Conversion Agent and Custodian and the Trustee hereby
accepts such appointments and each of the corporate trust office of the Trustee
in Los Angeles, California and the office or agency of the Trustee in the
Borough of Manhattan, The City of New York, State of New York (which shall
initially be State Street Bank and Trust Company, N.A., an Affiliate of the
Trustee located at 61 Broadway, Concourse Level, Corporate Trust Window, New
York, New York 10006), shall be considered as one such office or agency of the
Company for the aforesaid purposes.

      SECTION 2.04 Paying Agent to Hold Money in Trust. The Company shall
require each Paying Agent other than the Trustee to agree in writing that the
Paying Agent will hold in trust for the benefit of Securityholders or the
Trustee all money held by the Paying Agent for the payment of principal or
interest, and will notify the Trustee of any default by the Company in making
any such payment. While any such default continues, the Trustee may require a
Paying Agent to pay all money held by it to the Trustee. The Company at any time
may require a Paying Agent to pay all money held by it to the Trustee and to
account for any money disbursed by it. Upon payment over to the Trustee, the
Paying Agent (if other than the Company or an Affiliate of the Company) shall
have no further liability for the money. If the Company or an Affiliate of the
Company acts as Paying Agent, it shall segregate and hold in a separate trust
fund for the benefit of the Securityholders all money held by it as Paying
Agent.

      SECTION 2.05 Securityholder. The Trustee shall preserve in as current a
form as is reasonably practicable the most recent list available to it of the
names and addresses of Securityholders. If the Trustee is not the Registrar, the
Company shall furnish to the Trustee on or before each interest payment date and
at such other times as the Trustee may request in writing a list in such form
and as of such date as the Trustee may reasonably require of the names and
addresses of Securityholders.

      SECTION 2.06 Transfer and Exchange. When Securities are presented to the
Registrar or a co-registrar with a request to register a transfer or to exchange
them for an equal principal amount of Securities of other denominations, the
Registrar shall register the transfer or make the exchange if its requirements
for such transactions are met. To permit registrations of transfers and
exchanges, the Company shall issue and the Trustee shall authenticate Securities
at the Registrar's request. No service charge shall be made for any registration
of transfer or exchange (except as otherwise expressly permitted herein), but
the Company may require payment of a sum sufficient to cover any transfer tax or
similar governmental charge payable in connection therewith (other than any such
transfer tax or similar governmental charge payable upon exchanges pursuant to
Sections 2.10, 3.06, 3.08, 5.02 or 11.05 hereof).

      The Company shall not be required (i) to register the transfer of or
exchange Securities during a period beginning at the opening of business 15 days
before the day of any selection of Securities for redemption under Section 3.02
hereof and ending at the close of business on the day of selection, or (ii) to
exchange or register the transfer of any Security so selected for redemption in
whole or in part, except the unredeemed portion of any Security being redeemed
in part or (iii) to

                                      -11-
<PAGE>
register the transfer of or exchange Securities submitted for repurchase (and
not withdrawn) under Sections 4.08 or 4.09 hereof.

      The Trustee shall have no responsibility for any actions taken or not
taken by the Depositary.

      SECTION 2.07 Replacement Securities. If the holder of a Security claims
that the Security has been lost, destroyed or wrongfully taken or if such
Security is mutilated and is surrendered to the Trustee, the Company shall issue
and the Trustee shall authenticate a replacement Security if the Trustee's and
the Company's requirements are met. If required by the Trustee or the Company,
an indemnity bond must be sufficient in the judgment of both to protect the
Company, the Trustee, any Agent or any authenticating agent from any loss which
any of them may suffer if a Security is replaced. The Company may charge for its
expenses in replacing a Security.

      In case any such mutilated, destroyed, lost or stolen Security has become
or is about to become due and payable, or is about to be redeemed or purchased
by the Company pursuant to Article III hereof or converted into shares of Common
Stock pursuant to Article V hereof, the Company in its discretion may, instead
of issuing a new Security, pay, redeem, purchase or convert such Security, as
the case may be.

      Every replacement Security is an additional obligation of the Company.

      SECTION 2.08 Outstanding Securities. The Securities outstanding at any
time are all the Securities authenticated by the Trustee except for those
canceled by it, those delivered to it for cancellation, and those described in
this Section as not outstanding.

      If a Security is replaced, paid, redeemed, or purchased or converted
pursuant to Section 2.07 hereof, it ceases to be outstanding unless, in the case
of a replaced Security, the Trustee receives proof satisfactory to it that the
replaced Security is held by a bona fide purchaser.

      If Securities are considered paid under Section 4.01 hereof, they cease to
be outstanding and interest on them ceases to accrue.

      A Security does not cease to be outstanding because the Company or an
Affiliate of the Company holds the Security.

      SECTION 2.09 Treasury Securities. In determining whether the
Securityholders of the required principal amount of Securities have concurred in
any direction, waiver or consent, Securities owned by the Company or an
Affiliate of the Company shall be considered as though they are not outstanding,
except that for the purposes of determining whether the Trustee shall be
protected in relying on any such direction, waiver or consent, only Securities
which a Trust Officer knows are so owned shall be so disregarded.

                                      -12-
<PAGE>
      SECTION 2.10 Temporary Securities: Exchange of Global Security for
Certificated Securities.

            (a)   Until definitive Securities are ready for delivery, the
Company may prepare and the Trustee shall authenticate temporary Securities.
Temporary Securities shall be substantially in the form of definitive securities
but may have variations that the Company considers appropriate for temporary
Securities. Without unreasonable delay, the Company shall prepare and the
Trustee shall authenticate definitive Securities in exchange for temporary
Securities.

            (b)   Any Global Security or Securities deposited with the
Depositary or with the Trustee as Custodian for the Depositary pursuant to
Section 2.01 shall be transferred to the beneficial owners thereof in the form
of certificated securities only if such transfer complies with Section 2.06 and
(i) the Depositary notifies the Company that it is unwilling or unable to
continue as Depositary for such Global Security or if at any time such
Depositary ceases to be a "clearing agency" registered under the Exchange Act
and a successor Depositary is not appointed by the Company within 90 days of
such notice, or (ii) an Event of Default has occurred and is continuing.

            (c)   Any Global Security that is transferable to the beneficial
owners thereof in the form of certificated Securities pursuant to this Section
2.10 shall be surrendered by the Depositary to the Trustee to be so transferred,
in whole or from time to time in part, without charge, and the Trustee shall
authenticate and deliver, upon such transfer of each portion of such Global
Security, an equal aggregate principal amount at maturity of Securities of
authorized denominations in the form of certificated Securities. Any portion of
a Global Security transferred pursuant to this Section shall be executed,
authenticated and delivered only in denominations of $1,000 and any integral
multiple thereof and registered in such names as the Depositary shall direct.

            (d)   Prior to any transfer pursuant to Section 2.10(b), the
registered holder of a Global Security may grant proxies and otherwise authorize
any person, including Agent Members and persons that may hold interests through
Agent Members, to take any action which a holder is entitled to take under this
Indenture or the Securities.

            (e)   In the event of the occurrence of either of the events
specified in Section 2.10(b), the Company will promptly make available to the
Trustee a reasonable supply of certificated Securities in definitive form
without interest coupons.

      SECTION 2.11 Cancellation. The Company at any time may deliver Securities
to the Trustee for cancellation. The Registrar, Paying Agent and Conversion
Agent shall forward to the Trustee any Securities surrendered to them for
registration of transfer, redemption, purchase, conversion, exchange or payment.
The Trustee shall promptly cancel all Securities surrendered for registration of
transfer, redemption, purchase, conversion, exchange, payment, replacement or
cancellation and shall destroy all canceled Securities unless the Company
otherwise directs. The Company may not issue new Securities to replace
Securities that it has paid or that have been delivered to the Trustee for
cancellation or that any holder has converted.

                                      -13-
<PAGE>
      SECTION 2.12 Defaulted Interest. If the Company fails to make a payment of
interest, it shall pay such defaulted interest plus any interest payable on the
defaulted interest, in any lawful manner. It may pay such defaulted interest,
plus any such interest payable thereon, to the persons who are Securityholders
on a subsequent special record date. The Company shall fix any such record date
and payment date. At least 15 days before any such record date, the Company
shall mail to Securityholders a notice that states the record date, payment
date, and amount of such interest to be paid.

                                  ARTICLE III

                                   Redemption

      SECTION 3.01 Notices to Trustee. If the Company elects to redeem
Securities pursuant to Section 3.07 hereof, it shall notify the Trustee of the
redemption date and the principal amount of Securities to be redeemed. The
Company shall give each notice provided for in this Section 3.01 to the Trustee
at least 20 days before the redemption date (unless a shorter notice period
shall be satisfactory to the Trustee).

      SECTION 3.02 Selection of Securities to be Redeemed. If less than all the
Securities are to be redeemed, the Trustee shall select the Securities to be
redeemed by a method that complies with the requirements of the principal
national securities exchange, if any, on which the Securities are listed, or, if
the Securities are not so listed, on a pro rata basis. The Trustee shall make
the selection not more than 60 days and not less than 15 days before the
redemption date from Securities outstanding not previously called for
redemption. The Trustee may select for redemption portions of the principal of
Securities that have denominations larger than $1,000. Securities and portions
of them it selects shall be in amounts of $1,000 or integral multiples of
$1,000. Provisions of this Indenture that apply to Securities called for
redemption also apply to portions of Securities called for redemption. The
Trustee shall notify the Company promptly of the Securities or portions of
Securities to be called for redemption.

      If any Security selected for partial redemption is converted in part after
such selection, the converted portion of such Security shall be deemed (so far
as may be) to be the portion to be selected for redemption. The Securities (or
portions thereof) so selected shall be deemed duly selected for redemption for
all purposes hereof, notwithstanding that any such Security is converted in
whole or in part before the mailing of the notice of redemption. Upon any
redemption of less than all the Securities, the Company and the Trustee may
treat as outstanding any Securities surrendered for conversion during the period
15 days next preceding the mailing of a notice of redemption and need not treat
as outstanding any Security authenticated and delivered during such period in
exchange for the unconverted portion of any Security converted in part during
such period.

      SECTION 3.03 Notice of Redemption. At least 15 days but not more than 60
days before a redemption date, the Company shall mail a notice of redemption to
each holder whose Securities are to be redeemed at such holder's registered
address.

      The notice shall identify the Securities to be redeemed and shall state:

                                      -14-
<PAGE>
            (a)   the redemption date;

            (b)   the redemption price;

            (c)   if any Security is being redeemed in part, the portion of the
principal amount of such Security to be redeemed and that, after the redemption
date, upon cancellation of such Security, a new Security or Securities in
principal amount equal to the unredeemed portion will be issued in the name of
the holder thereof;

            (d)   the name and address of the Paying Agent;

            (e)   that Securities called for redemption must be surrendered to
the Paying Agent to collect the redemption price plus accrued interest;

            (f)   that, unless the Company defaults in making such redemption
payment or the Paying Agent is prohibited from making such payment pursuant to
the terms of this Indenture, by law or otherwise, interest on Securities called
for redemption ceases to accrue on and after the redemption date; and

            (g)   the paragraph of the Securities pursuant to which the
Securities called for redemption are being redeemed.

      Such notice shall also state the current Conversion Price and the date on
which the right to convert such Securities or portions thereof into Common Stock
of the Company will expire.

      At the Company's request, the Trustee shall give notice of redemption in
the Company's name and at its expense.

      SECTION 3.04 Effect of Notice of Redemption. Once notice of redemption is
mailed, Securities called for redemption become due and payable on the
redemption date at the price set forth in the Security.

      SECTION 3.05 Deposit of Redemption Price. On or before the redemption
date, the Company shall deposit with the Trustee or with the Paying Agent money
sufficient to pay the redemption price of and accrued interest, up to but not
including the redemption date on all Securities to be redeemed on that date
(subject to the right of holders of record on the relevant record date to
receive interest, due on an interest payment date) unless theretofore converted
into Common Stock pursuant to the provisions hereof. The Trustee or the Paying
Agent shall return to the Company any money not required for that purpose.

      SECTION 3.06 Securities Redeemed in Part. Upon surrender of a Security
that is redeemed in part, the Company shall issue and the Trustee shall
authenticate for the holder at the expense of the Company a new Security equal
in principal amount to the unredeemed portion of the Security surrendered.

                                      -15-
<PAGE>
      SECTION 3.07 Optional Redemption. The Company may redeem all or any
portion of the Securities, upon the terms and at the redemption price set forth
in each of the Securities. Any redemption pursuant to this Section 3.07 shall be
made pursuant to the provisions of Section 3.01 through 3.06 hereof.

      SECTION 3.08 Designated Event Offer.

            (a)   In the event that, pursuant to Section 4.08 hereof, the
Company shall commence a Designated Event Offer, the Company shall follow the
procedures in this Section 3.08.

            (b)   The Designated Event Offer shall remain open for a period
specified by the Company which shall be no less than 30 calendar days and no
more than 40 calendar days following its commencement on the date of the mailing
of notice in accordance with Section 4.08 hereof (the "Commencement Date"),
except to the extent that a longer period is required by applicable law (the
"Tender Period"). Upon the expiration of the Tender Period (the "Designated
Event Payment Date"), the Company shall purchase the principal amount of
Securities required to be purchased pursuant to Section 4.08 hereof (the "Offer
Amount").

            (c)   If the Designated Event Payment Date is on or after an
interest payment record date and on or before the related interest payment date,
any accrued interest, to the related interest payment date will be paid to the
person in whose name a Security is registered at the close of business on such
record date, and no additional interest, will be payable to Securityholders who
tender Securities pursuant to the Designated Event Offer.

            (d)   The Company shall provide the Trustee with written notice of
the Designated Event Offer at least 10 Business Days before the Commencement
Date.

            (e)   On or before the Commencement Date, the Company or the Trustee
(at the request and expense of the Company) shall send, by first class mail, a
notice to each of the Securityholders, which shall govern the terms of the
Designated Event Offer and shall state:

                  (i)   that the Designated Event Offer is being made pursuant
to this Section 3.08 and Section 4.08 hereof and that all Securities tendered
will be accepted for payment;

                  (ii)  the purchase price (as determined in accordance with
Section 4.08 hereof), the length of time the Designated Event Offer will remain
open and the Designated Event Payment Date;

                  (iii) that any Security or portion thereof not tendered or
accepted for payment will continue to accrue interest;

                  (iv)  that, unless the Company defaults in the payment of the
Designated Event Payment, any Security or portion thereof accepted for payment
pursuant to the Designated Event Offer shall cease to accrue interest, after the
Designated Event Payment Date;

                                      -16-
<PAGE>
                  (v)   that Securityholders electing to have a Security or
portion thereof purchased pursuant to any Designated Event Offer will be
required to surrender the Security, with the form entitled "Option of
Securityholder To Elect Purchase" on the reverse of the Security completed, to
the Paying Agent at the address specified in the notice prior to the close of
business on the third Business Day preceding the Designated Event Payment Date;

                  (vi)  that Securityholders will be entitled to withdraw their
election if the Paying Agent receives, not later than the close of business on
the second Business Day preceding the Designated Event Payment Date, or such
longer period as may be required by law, a letter or a telegram, telex,
facsimile transmission (receipt of which is confirmed and promptly followed by a
letter) setting forth the name of the Securityholder, the principal amount of
the Security or portion thereof the Securityholder delivered for purchase and a
statement that such Securityholder is withdrawing his election to have the
Security or portion thereof purchased; and

                  (vii) that Securityholders whose Securities are being
purchased only in part will be issued new Securities equal in principal amount
to the unpurchased portion of the Securities surrendered, which unpurchased
portion must be equal to $1,000 in principal amount or an integral multiple
thereof.

      In addition, the notice shall contain all instructions and materials that
the Company shall reasonably deem necessary to enable such Securityholders to
tender Securities pursuant to the Designated Event Offer.

            (f) On or prior to the Designated Event Payment Date, the Company
shall irrevocably deposit with the Trustee or a Paying Agent in immediately
available funds an amount equal to the Offer Amount to be held for payment in
accordance with the terms of this Section 3.08. On the Designated Event Payment
Date, the Company shall, to the extent lawful, (i) accept for payment the
Securities or portions thereof tendered pursuant to the Designated Event Offer,
(ii) deliver or cause to be delivered to the Trustee Securities so accepted and
(iii) deliver to the Trustee an Officers' Certificate stating such Securities or
portions thereof have been accepted for payment by the Company in accordance
with the terms of this Section 3.08. The Paying Agent shall promptly (but in any
case not later than five calendar days after the Designated Event Payment Date)
mail or deliver to each tendering Securityholder an amount equal to the purchase
price of the Securities tendered by such Securityholder, and the Trustee shall
promptly authenticate and mail or deliver to such Securityholders a new Security
equal in principal amount to any unpurchased portion of the Security
surrendered, if any; provided, that each new Security shall be in a principal
amount of $1,000 or an integral multiple thereof. Any Securities not so accepted
shall be promptly mailed or delivered by or on behalf of the Company to the
holder thereof. The Company will publicly announce the results of the Designated
Event Offer on, or as soon as practicable after, the Designated Event Payment
Date.

            (g) The Designated Event Offer shall be made by the Company in
compliance with all applicable provisions of the Exchange Act, and all
applicable tender offer rules promulgated thereunder, and shall include all
instructions and materials that the Company shall reasonably deem necessary to
enable such Securityholders to tender their Securities.

                                      -17-
<PAGE>
      SECTION 3.09 Conversion Arrangement on Underwritten Call for Redemption.
In connection with any redemption of Securities, the Company may arrange for the
purchase and conversion of any Securities by an arrangement with one or more
investment bankers or other purchasers to purchase such Securities by paying to
the Trustee in trust for the holders, on or before the date fixed for
redemption, an amount not less than the applicable redemption price, together
with interest accrued to (but excluding) the date fixed for redemption, of such
Securities. Notwithstanding anything to the contrary contained in this Article
III, the obligation of the Company to pay the redemption price of such
Securities, together with interest accrued to (but excluding) the date fixed for
redemption, shall be deemed to be satisfied and discharged to the extent such
amount is so paid by the purchasers. If such an agreement is entered into, a
copy of which will be filed with the Trustee prior to the date fixed for
redemption, any Securities not duly surrendered for conversion by the holders
thereof may, at the option of the Company, be deemed, to the fullest extent
permitted by law, acquired by such purchasers from such holders and
(notwithstanding anything to the contrary contained in Article V) surrendered by
such purchasers for conversion, all as of immediately prior to the close of
business on the date fixed for redemption (and the right to convert any such
Securities shall be deemed to have been extended through such time), subject to
payment of the above amount as aforesaid. At the direction of the Company, the
Trustee shall hold and dispose of any such amount paid to it in the same manner
as it would monies deposited with it by the Company for the redemption of
Securities. Without the Trustee's prior written consent, no arrangement between
the Company and such purchasers for the purchase and conversion of any
Securities shall increase or otherwise affect any of the powers, duties,
responsibilities or obligations of the Trustee as set forth in this Indenture,
and the Company agrees to indemnify the Trustee from, and hold it harmless
against, any loss, liability or expense arising out of or in connection with any
such arrangement for the purchase and conversion of any Securities between the
Company and such purchasers to which the Trustee has not consented in writing,
including the costs and expenses incurred by the Trustee in the defense of any
claim or liability arising out of or in connection with the exercise or
performance of any of its powers, duties, responsibilities or obligations under
this Indenture.

                                   ARTICLE IV

                                    Covenants

      SECTION 4.01 Payment of Securities. The Company shall pay the principal
of, premium, if any, and interest on the dates and in the manner provided in the
Securities. Principal, premium, if any, and interest, shall be considered paid
on the date due if the Paying Agent (other than the Company or an Affiliate of
the Company) holds on that date money designated for and sufficient to pay all
principal, premium, if any, and interest, then due and such Paying Agent is not
prohibited from paying such money to the Securityholders on that date pursuant
to the terms of this Indenture. To the extent lawful, the Company shall pay
interest (including post-petition interest in any proceeding under any
Bankruptcy Law) on overdue installments of interest (without regard to any
applicable grace period) at the rate borne by the Securities, compounded
semiannually.

                                      -18-
<PAGE>
      SECTION 4.02 SEC Reports. Whether or not required by the rules and
regulations of the SEC, so long as any Securities are outstanding, the Company
will file with the SEC and the Trustee, and if requested by any holders of
Securities, the Trustee shall furnish to the holders of Securities all quarterly
and annual financial information required to be contained in a filing with the
SEC on Forms 10-Q and 10-K, including a "Management's Discussion and Analysis of
Financial Conditions and Results of Operations" and, with respect to annual
information only, a report thereon by the Company's certified independent
accountants.

      SECTION 4.03 Compliance Certificate. The Company shall deliver to the
Trustee, within 120 days after the end of each fiscal year of the Company, an
Officers' Certificate stating that a review of the activities of the Company and
its subsidiaries during the preceding fiscal year has been made under the
supervision of the signing Officers with a view to determining whether the
Company has kept, observed, performed and fulfilled its obligations under, and
complied with the covenants and conditions contained in, this Indenture, and
further stating, as to each such Officer signing such certificate, that to the
best of such Officer's knowledge the Company has kept, observed, performed and
fulfilled each and every covenant, and complied with the covenants and
conditions contained in this Indenture and is not in default in the performance
or observance of any of the terms, provisions and conditions hereof (or if a
Default or Event of Default shall have occurred, describing all such Defaults or
Events of Default of which such Officer may have knowledge) and that to the best
of such Officer's knowledge no event has occurred and remains in existence by
reason of which payments on account of the principal or of interest are
prohibited.

      One of the Officers signing such Officers' Certificate shall be either the
Company's principal executive officer, principal financial officer or principal
accounting officer.

      The Company will, so long as any of the Securities are outstanding,
deliver to the Trustee, forthwith upon becoming aware of:

      (a) any Default, Event of Default or default in the performance of any
covenant, agreement or condition contained in this Indenture; or

      (b) any event of default under any other mortgage, indenture or instrument
as that term is used in Section 8.01(f), an Officers' Certificate specifying
such Default, Event of Default or default.

      SECTION 4.04 Stay, Extension and Usury Law. The Company covenants (to the
extent that it may lawfully do so) that it will not at any time insist upon,
plead, or in any manner whatsoever claim or take the benefit or advantage of,
any stay, extension or usury law wherever enacted, now or at any time hereafter
in force, which may affect the covenants or the performance of this Indenture;
and the Company (to the extent it may lawfully do so) hereby expressly waives
all benefit or advantage of any such law, and covenants that it will not, by
resort to any such law, hinder, delay or impede the execution of any power
herein granted to the Trustee, but will suffer and permit the execution of every
such power as though no such law has been enacted.

                                      -19-
<PAGE>
      SECTION 4.05 Corporate Existence. Except as provided in Article VII
hereof, the Company will do or cause to be done all things necessary to preserve
and keep in full force and effect its corporate existence and the corporate,
partnership or other existence of each Subsidiary of the Company in accordance
with the respective organizational documents of each Subsidiary and the rights
(charter and statutory), licenses and franchises of the Company and its
Subsidiaries; provided, however, that the Company shall not be required to
preserve any such right, license or franchise, or the corporate, partnership or
other existence of any Subsidiary, if the Company shall determine that the
preservation thereof is no longer desirable in the conduct of the business of
the Company and its Subsidiaries taken as a whole and that the loss thereof is
not adverse in any material respect to the Securityholders.

      SECTION 4.06 Maintenance of Properties. The Company will cause all
properties used or useful in the conduct of its business or the business of any
Subsidiary to be maintained and kept in good condition, repair and working order
and supplied with all necessary equipment and will cause to be made all
necessary repairs, renewals, replacements, betterments and improvements thereof,
all as in the judgment of the Company may be necessary so that the business
carried on in connection therewith may be properly and advantageously conducted
at all times; provided, however, that nothing in this Section shall prevent the
Company from discontinuing the operation or maintenance of any of such
properties if such discontinuance is, in the judgment of the Company, desirable
in the conduct of its business or the business of any Subsidiary and not
disadvantageous in any material respect to the holders.

      SECTION 4.07 Payment of Taxes and Other Claims. The Company will pay or
discharge, or cause to be paid or discharged, before the same may become
delinquent, (i) all taxes, assessments and governmental charges levied or
imposed upon the Company or any Subsidiary or upon the income, profits or
property of the Company or any Subsidiary, (ii) all claims for labor, materials
and supplies which, if unpaid, might by law become a lien or charge upon the
property of the Company or any Subsidiary, and (iii) all stamps and other
duties, if any, which may be imposed by the United States or any political
subdivision thereof or therein in connection with the issuance, transfer,
exchange or conversion of any Securities or with respect to this Indenture;
provided, however, that, in the case of clauses (i) and (ii), the Company shall
not be required to pay or discharge or cause to be paid or discharged any such
tax, assessment, charge or claim (A) if the failure to do so will not, in the
aggregate, have a material adverse impact on the Company, or (B) if the amount,
applicability or validity is being contested in good faith by appropriate
proceedings.

      SECTION 4.08 Designated Event. Upon the occurrence of a Designated Event,
each holder of Securities shall have the right, in accordance with this Section
4.08 and Section 3.08 hereof, to require the Company to repurchase all or any
part (equal to $1,000 or an integral multiple thereof) of such holder's
Securities pursuant to the terms of Section 3.08 (the "Designated Event Offer")
at a purchase price equal to 101% of the principal amount thereof, plus accrued
and unpaid interest to the Designated Event Payment Date (the "Designated Event
Payment").

      Within 30 days following any Designated Event, the Company shall mail to
each holder the notice provided by Section 3.08(e).

                                      -20-
<PAGE>
      SECTION 4.09 Triggering Distribution. Upon the occurrence of a Triggering
Distribution, each holder of Securities shall have the right, in accordance with
this Section 4.09 and Article XIII hereof, to require the Company to repurchase
all or any part (equal to $1,000 or an integral multiple thereof) of such
holder's Securities pursuant to the terms of Article XIII hereof (the
"Repurchase Offer") at a purchase price equal to 100% of the principal amount
thereof, together with any accrued and unpaid interest (the "Repurchase
Payment") to the repurchase date, which repurchase date shall be on or prior to
the distribution date for such Triggering Distribution (the "Repurchase Payment
Date"). Notwithstanding anything herein to the contrary, in the event that such
Triggering Distribution is not so paid or made, all of such holder's rights to
require the Company to repurchase their Securities pursuant to this Section 4.09
and Article XIII hereof as a result of such Triggering Distribution shall
terminate and any pending Repurchase Offer shall be rescinded.

      SECTION 4.10 Further Instruments and Acts. Upon request of the Trustee,
the Company will execute and deliver such further instruments and do such
further acts as may be reasonably necessary or proper to carry out more
effectively the purposes of this Indenture.

                                   ARTICLE V

                                   Conversion

      SECTION 5.01 Conversion Privilege. A holder of a Security may convert the
principal amount thereof (or any portion thereof that is an integral multiple of
$1,000) into fully paid and nonassessable shares of Common Stock of the Company
at any time prior to the close of business (New York time) on the maturity date
of the Security at the Conversion Price then in effect, except that, with
respect to any Security called for redemption, such conversion right shall
terminate at the close of business (New York time) on the Business Day
immediately preceding the redemption date (unless the Company shall default in
making the redemption payment when it becomes due, in which case the conversion
price shall terminate on the date such default is cured). A Security in respect
of which a holder has delivered an "Option of Securityholder to Elect Purchase"
form set forth on Exhibit A hereto exercising the option of such holder to
require the Company to purchase such Security may be converted only if the
notice of exercise is withdrawn as provided in accordance with Section 3.08
hereof. The number of shares of Common Stock issuable upon conversion of a
Security is determined by dividing the principal amount of the Security
converted by the conversion price in effect on the Conversion Date (the
"Conversion Price").

      The initial Conversion Price is stated in paragraph 10 of the Securities
and is subject to adjustment as provided in this Article V.

      Provisions of this Indenture that apply to conversion of all of a Security
also apply to conversion of a portion of it. A holder of Securities is not
entitled to any rights of a holder of Common Stock until such holder of
Securities has converted such Securities into Common Stock, and only to the
extent that such Securities are deemed to have been converted into Common Stock
under this Article V.

                                      -21-
<PAGE>
      SECTION 5.02 Conversion Procedure. To convert a Security, a holder must
satisfy the requirements in paragraph 10 of the Securities. The date on which
the holder satisfies all of those requirements is the conversion date (the
"Conversion Date"). As soon as practicable after the Conversion Date, the
Company shall deliver to the holder through the Conversion Agent a certificate
for the number of whole shares of Common Stock issuable upon the conversion and
a check for any fractional share determined pursuant to Section 5.03. The person
in whose name the certificate is registered shall become the shareholder of
record on the Conversion Date and, as of such date, such person's rights as a
Securityholder with respect to the converted Security shall cease; provided,
however, that no surrender of a Security on any date when the stock transfer
books of the Company shall be closed shall be effective to constitute the person
entitled to receive the shares of Common Stock upon such conversion as the
shareholder of record of such shares of Common Stock on such date, but such
surrender shall be effective to constitute the person entitled to receive such
shares of Common Stock as the shareholder of record thereof for all purposes at
the close of business on the next succeeding day on which such stock transfer
books are open; provided further, however, that such conversion shall be at the
Conversion Price in effect on the date that such Security shall have been
surrendered for conversion, as if the stock transfer books of the Company had
not been closed.

      No payment or adjustment will be made for accrued and unpaid interest on a
converted Security or for dividends or distributions on shares of Common Stock
issued upon conversion of a Security, but if any holder surrenders a Security
for conversion after the close of business on the record date for the payment of
an installment of interest and prior to the opening of business on the next
interest payment date, then, notwithstanding such conversion, the interest
payable on such interest payment date shall be paid to the holder of such
Security on such record date. In such event, unless such Security has been
called for redemption on or prior to such interest payment date, such Security,
when surrendered for conversion, must be accompanied by payment in funds
acceptable to the Company of an amount equal to the interest payable on such
interest payment date on the portion so converted.

      If a holder converts more than one Security at the same time, the number
of whole shares of Common Stock issuable upon the conversion shall be based on
the total principal amount of Securities converted.

      Upon surrender of a Security that is converted in part, the Trustee shall
authenticate for the holder a new Security equal in principal amount to the
unconverted portion of the Security surrendered.

      SECTION 5.03 Fractional Shares. The Company will not issue fractional
shares of Common Stock upon conversion of a Security. In lieu thereof, the
Company will pay an amount in cash based upon the Daily Market Price of the
Common Stock on the Trading Day prior to the date of conversion.

      SECTION 5.04 Taxes on Conversion. The issuance of certificates for shares
of Common Stock upon the conversion of any Security shall be made without charge
to the converting Securityholder for such certificates or for any tax in respect
of the issuance of such certificates, and such certificates shall be issued in
the respective names of, or in such names as may be directed by,

                                      -22-
<PAGE>
the holder or holders of the converted Security; provided, however, that in the
event that certificates for shares of Common Stock are to be issued in a name
other than the name of the holder of the Security converted, such Security, when
surrendered for conversion, shall be accompanied by an instrument of transfer,
in form satisfactory to the Company, duly executed by the registered holder
thereof or his duly authorized attorney; and provided further, however, that the
Company shall not be required to pay any tax which may be payable in respect of
any transfer involved in the issuance and delivery of any such certificates in a
name other than that of the holder of the converted Security, and the Company
shall not be required to issue or deliver such certificates unless or until the
person or persons requesting the issuance thereof shall have paid to the Company
the amount of such tax or shall have established to the satisfaction of the
Company that such tax has been paid or is not applicable.

      SECTION 5.05 Company to Provide Stock. The Company shall at all times
reserve and keep available, free from preemptive rights, out of its authorized
but unissued Common Stock, solely for the purpose of issuance upon conversion of
Securities as herein provided, a sufficient number of shares of Common Stock to
permit the conversion of all outstanding Securities for shares of Common Stock.

      All shares of Common Stock which may be issued upon conversion of the
Securities shall be duly authorized, validly issued, fully paid and
nonassessable when so issued.

      SECTION 5.06 Adjustment of Conversion Price. The Conversion Price shall be
subject to adjustment from time to time as follows:

            (a)   In case the Company shall (1) pay a dividend in shares of
Common Stock to holders of Common Stock, (2) make a distribution in shares of
Common Stock to holders of Common Stock, (3) subdivide its outstanding shares of
Common Stock into a greater number of shares of Common Stock or (4) combine its
outstanding shares of Common Stock into a smaller number of shares of Common
Stock, the Conversion Price in effect immediately prior to such action shall be
adjusted so that the holder of any Security thereafter surrendered for
conversion shall be entitled to receive the number of shares of Common Stock
which he would have owned immediately following such action had such Securities
been converted immediately prior thereto. Any adjustment made pursuant to this
subsection (a) shall become effective immediately after the record date in the
case of a dividend or distribution and shall become effective immediately after
the effective date in the case of a subdivision or combination.

            (b)   In case the Company shall issue rights or warrants to
substantially all holders of Common Stock entitling them (for a period
commencing no earlier than the record date for the determination of holders of
Common Stock entitled to receive such rights or warrants and expiring not more
than 45 days after such record date) to subscribe for or purchase shares of
Common Stock (or securities convertible into Common Stock) at a price per share
less than the Current Market Price (as determined pursuant to subsection (f)
below) of the Common Stock on such record date, the Conversion Price shall be
adjusted so that the same shall equal the price determined by multiplying the
Conversion Price in effect immediately prior to such record date by a fraction
of which the numerator shall be the number of shares of Common Stock outstanding
on such record date, plus the

                                      -23-
<PAGE>
number of shares of Common Stock which the aggregate offering price of the
offered shares of Common Stock (or the aggregate conversion price of the
convertible securities so offered) would purchase at such Current Market Price,
and of which the denominator shall be the number of shares of Common Stock
outstanding on such record date plus the number of additional shares of Common
Stock offered (or into which the convertible securities so offered are
convertible). Such adjustments shall become effective immediately after such
record date.

            (c)   In case the Company shall distribute to all holders of Common
Stock shares of any class of Capital Stock of the Company (other than Common
Stock referred to in subsection (a) above), evidences of indebtedness or other
assets (other than cash dividends out of current or retained earnings), or shall
distribute to substantially all holders of Common Stock rights or warrants to
subscribe for securities (other than those Securities referred to in subsection
(b) above), then in each such case the Conversion Price shall be adjusted so
that the same shall equal the price determined by multiplying the Conversion
Price in effect immediately prior to the date of such distribution by a fraction
of which the numerator shall be the Current Market Price (determined as provided
in subsection (f) below) of the Common Stock on the record date mentioned below
less the then fair market value (as determined by the Board of Directors, whose
determination shall be conclusive evidence of such fair market value and
described in a Board Resolution) of the portion of the assets so distributed or
of such subscription rights or warrants applicable to one share of Common Stock,
and of which the denominator shall be such Current Market Price of the Common
Stock. Such adjustment shall become effective immediately after the record date
for the determination of the holders of Common Stock entitled to receive such
distribution. Notwithstanding the foregoing, in case the Company shall issue
rights or warrants to subscribe for additional shares of the Company's capital
stock (other than those referred to in subsection (b) above) ("Rights") to
substantially all holders of Common Stock, the Company may, in lieu of making
any adjustment pursuant to this Section 5.06, make proper provision so that each
holder of a Security who converts such Security (or any portion thereof) after
the record date for such distribution and prior to the expiration or redemption
of the Rights shall be entitled to receive upon such conversion, in addition to
the shares of Common Stock issuable upon such conversion (the "Conversion
Shares"), a number of Rights to be determined as follows: (i) if such conversion
occurs on or prior to the date for the distribution to the holders of Rights of
separate certificates evidencing such Rights (the "Distribution Date"), the same
number of Rights to which a holder of a number of shares of Common Stock equal
to the number of Conversion Shares is entitled at the time of such conversion in
accordance with the terms and provisions of and applicable to the Rights; and
(ii) if such conversion occurs after the Distribution Date, the same number of
Rights to which a holder of the number of shares of Common Stock into which the
principal amount of the Security so converted was convertible immediately prior
to the Distribution Date would have been entitled on the Distribution Date in
accordance with the terms and provisions of and applicable to the Rights. In the
event the Company implements a shareholder rights plan, such rights plan must
provide that upon conversion of the Securities the holders will receive, in
addition to the Common Stock issuable upon such conversion, such rights (whether
or not such rights have separated from the Common Stock at the time of such
conversion).

                                      -24-
<PAGE>
            (d) In case the Company shall, by dividend or otherwise, at any time
distribute to all holders of its Common Stock cash (including any distributions
of cash out of current or retained earnings of the Company but excluding any
cash that is distributed as part of a distribution requiring a Conversion Price
adjustment pursuant to paragraph (c) of this Section) in an aggregate amount
that, together with the sum of (x) the aggregate amount of any other
distributions to all holders of its Common Stock made in cash plus (y) all
Excess Payments, in each case made within the 12 months preceding the date fixed
for determining the shareholders entitled to such distribution (the
"Distribution Record Date") and in respect of which no Conversion Price
adjustment pursuant to paragraphs (c) or (e) of this Section or this paragraph
(d) has been made, exceeds 15% of the product of the Current Market Price per
share (determined as provided in paragraph (f) of this Section) of the Common
Stock on the Distribution Record Date multiplied by the number of shares of
Common Stock outstanding on the Distribution Record Date (excluding shares held
in the treasury of the Company), the Conversion Price shall be reduced so that
the same shall equal the price determined by multiplying such Conversion Price
in effect immediately prior to the effectiveness of the Conversion Price
reduction contemplated by this paragraph (d) by a fraction of which the
numerator shall be the Current Market Price per share (determined as provided in
paragraph (f) of this Section) of the Common Stock on the Distribution Record
Date less the amount of such cash and other consideration (including any Excess
Payments) so distributed applicable to one share of Common Stock (equal to the
aggregate amount of such cash and other consideration (including any Excess
Payments) divided by the number of shares of Common Stock outstanding on the
Distribution Record Date) and the denominator shall be such Current Market Price
per share (determined as provided in paragraph (f) of this Section) of the
Common Stock on the Distribution Record Date, such reduction to become effective
immediately prior to the opening of business on the day following the
Distribution Record Date.

            (e) In case a tender offer or other negotiated transaction made by
the Company or any Subsidiary of the Company for all or any portion of the
Common Stock shall be consummated, if an Excess Payment is made in respect of
such tender offer or other negotiated transaction and the amount of such Excess
Payment, together with the sum of (x) the aggregate amount of all Excess
Payments plus (y) the aggregate amount of all distributions to all holders of
the Common Stock made in cash (including any distributions of cash out of
current or retained earnings of the Company), in each case made within the 12
months preceding the date of payment of such current negotiated transaction
consideration or expiration of such current tender offer, as the case may be
(the "Purchase Date"), and as to which no adjustment pursuant to paragraph (c)
or paragraph (d) of this Section or this paragraph (e) has been made, exceeds
15% of the product of the Current Market Price per share (determined as provided
in paragraph (f) of this Section) of the Common Stock on the Purchase Date
multiplied by the number of shares of Common Stock outstanding (including any
tendered shares but excluding any shares held in the treasury of the Company or
any Subsidiary of the Company) on the Purchase Date, the Conversion Price shall
be reduced so that the same shall equal the price determined by multiplying such
Conversion Price in effect immediately prior to the effectiveness of the
Conversion Price reduction contemplated by this paragraph (e) by a fraction of
which the numerator shall be the Current Market Price per share (determined as
provided in paragraph (f) of this Section) of the Common Stock on the Purchase
Date less the amount of such Excess Payments and such cash distributions, if
any, applicable to one share of Common Stock

                                      -25-
<PAGE>
(equal to the aggregate amount of such Excess Payments and such cash
distributions divided by the number of shares of Common Stock outstanding on the
Purchase Date) and the denominator shall be such Current Market Price per share
(determined as provided in paragraph (f) of this Section) of the Common Stock on
the Purchase Date, such reduction to become effective immediately prior to the
opening of business on the day following the Purchase Date.

      (f) The "Current Market Price" per share of Common Stock on any date shall
be deemed to be the average of the Daily Market Prices for the shorter of (i) 30
consecutive Business Days ending on the last full Trading Day on the exchange or
market referred to in determining such Daily Market Prices prior to the time of
determination or (ii) the period commencing on the date next succeeding the
first public announcement of the issuance of such rights or such warrants or
such other distribution or such negotiated transaction through such last full
Trading Day on the exchange or market referred to in determining such Daily
Market Prices prior to the time of determination.

      (g) In any case in which this Section 5.06 shall require that an
adjustment be made immediately following a record date for an event, the Company
may elect to defer, until such event, issuing to the holder of any Security
converted after such record date the shares of Common Stock and other Capital
Stock of the Company issuable upon such conversion over and above the shares of
Common Stock and other Capital Stock of the Company issuable upon such
conversion only on the basis of the Conversion Price prior to adjustment; and,
in lieu of the shares the issuance of which is so deferred, the Company shall
issue or cause its transfer agents to issue due bills or other appropriate
evidence of the right to receive such shares.

      SECTION 5.07 No Adjustment. No adjustment in the Conversion Price
shall be required until cumulative adjustments amount to 1% or more of the
Conversion Price as last adjusted; provided, however, that any adjustments which
by reason of this Section 5.07 are not required to be made shall be carried
forward and taken into account in any subsequent adjustment. All calculations
under this Article V shall be made to the nearest cent or to the nearest
one-hundredth of a share, as the case may be. No adjustment need be made for
rights to purchase Common Stock pursuant to a Company plan for reinvestment of
dividends or interest. No adjustment need be made for a change in the par value
or no par value of the Common Stock.

      SECTION 5.08 Other Adjustments. In the event that, as a result of an
adjustment made pursuant to Section 5.06 above, the holder of any Security
thereafter surrendered for conversion shall become entitled to receive any
shares of Capital Stock of the Company other than shares of its Common Stock,
thereafter the Conversion Price of such other shares so receivable upon
conversion of any Securities shall be subject to adjustment from time to time in
a manner and on terms as nearly equivalent as practicable to the provisions with
respect to Common Stock contained in this Article V.

      In the event that shares of Common Stock are not delivered after the
expiration of any of the rights or warrants referred to in Section 5.06(b) and
Section 5.06(c) hereof, the Conversion Price shall be readjusted to the
Conversion Price which would otherwise be in effect had the adjustment made upon
the issuance of such rights or warrants been made on the basis of delivery of
only the number of shares of Common Stock actually delivered.

                                      -26-
<PAGE>
      SECTION 5.09 Adjustments for Tax Purposes. The Company may, at its option,
make such reductions in the Conversion Price, in addition to those required by
Section 5.06 above, as it determines to be advisable in order that any stock
dividend, subdivision of shares, distribution of rights to purchase stock or
securities or distribution of securities convertible into or exchangeable for
stock made by the Company to its shareholders will not be taxable to the
recipients thereof

      SECTION 5.10 Adjustments by the Company. The Company from time to
time may, to the extent permitted by law, reduce the Conversion Price by any
amount for any period of at least 20 days, in which case the Company shall give
at least 15 days' notice of such reduction in accordance with Section 5.11, if
the Board of Directors has made a determination that such reduction would be in
the best interests of the Company, which determination shall be conclusive.

      SECTION 5.11 Notice of Adjustment. Whenever the Conversion Price is
adjusted, the Company shall promptly mail to Securityholders at the addresses
appearing on the Registrar's books a notice of the adjustment and file with the
Trustee an Officers' Certificate briefly stating the facts requiring the
adjustment and the manner of computing it. The certificate shall be conclusive
evidence of the correctness of such adjustment.

      SECTION 5.12 Notice of Certain Transactions. In the event that:

            (1) the Company takes any action which would require an adjustment
      in the Conversion Price;

            (2) the Company takes any action that would require a supplemental
      indenture pursuant to Section 5.13; or

            (3) there is a dissolution or liquidation of the Company; a holder
      of a Security may wish to convert such Security into shares of Common
      Stock prior to the record date for or the effective date of the
      transaction so that he may receive the rights, warrants, securities or
      assets which a holder of shares of Common Stock on that date may receive.
      Therefore, the Company shall mail a notice to Securityholders at the
      addresses appearing on the Registrar's books and deliver to the Trustee an
      Officers' Certificate, in each case stating the proposed record or
      effective date, as the case may be. The Company shall mail the notice and
      deliver such Officers' Certificate at least 15 days before such date;
      however, failure to mail such notice or any defect therein shall not
      affect the validity of any transaction referred to in clause (1), (2) or
      (3) of this Section 5.12.

      SECTION 5.13 Effect of Reclassifications, Consolidations, Mergers or Sales
on Conversion Privilege. If any of the following shall occur, namely: (i) any
reclassification or change of outstanding shares of Common Stock issuable upon
conversion of Securities (other than a change in par value, or from par value to
no par value, or from no par value to par value, or as a result of a subdivision
or combination), (ii) any consolidation or merger to which the Company is a
party other than a merger in which the Company is the continuing corporation and
which does not result in any reclassification of, or change (other than a change
in name, or par value, or from par value to no par value, or from no par value
to par value or as a result of a subdivision or combination) in,

                                      -27-
<PAGE>
outstanding shares of Common Stock or (iii) any sale or conveyance of all or
substantially all of the property or business of the Company as an entirety,
then the Company, or such successor or purchasing Corporate Entity, as the case
may be, shall, as a condition precedent to such reclassification, change,
consolidation, merger, sale or conveyance, execute and deliver to the Trustee a
supplemental indenture in form satisfactory to the Trustee providing that the
holder of each Security then outstanding shall have the right to convert such
Security into the kind and amount of shares of stock and other securities and
property (including cash) receivable upon such reclassification, change,
consolidation, merger, sale or conveyance by a holder of the number of shares of
Common Stock deliverable upon conversion of such Security immediately prior to
such reclassification, change, consolidation, merger, sale or conveyance. Such
supplemental indenture shall provide for adjustments of the Conversion Price
which shall be as nearly equivalent as may be practicable to the adjustments of
the Conversion Price provided for in this Article V. The foregoing, however,
shall not in any way affect the right a holder of a Security may otherwise have,
pursuant to clause (ii) of the last sentence of subsection (c) of Section 5.06,
to receive Rights upon conversion of a Security. If, in the case of any such
consolidation, merger, sale or conveyance, the stock or other securities and
property (including cash) receivable thereupon by a holder of Common Stock
includes shares of stock or other securities and property of a corporation other
than the successor or purchasing corporation, as the case may be, in such
consolidation, merger, sale or conveyance, then such supplemental indenture
shall also be executed by such other corporation and shall contain such
additional provisions to protect the interests of the holders of the Securities
as the Board of Directors shall reasonably consider necessary by reason of the
foregoing. The provision of this Section 5.13 shall similarly apply to
successive consolidations, mergers, sales or conveyances.

      In the event the Company shall execute a supplemental indenture pursuant
to this Section 5.13, the Company shall promptly file with the Trustee an
Officers' Certificate briefly stating the reasons therefor, the kind or amount
of shares of stock or securities or property (including cash) receivable by
holders of the Securities upon the conversion of their Securities after any such
reclassification, change, consolidation, merger, sale or conveyance and any
adjustment to be made with respect thereto.

      SECTION 5.14 Trustee's Disclaimer. The Trustee has no duty to
determine when an adjustment under this Article V should be made, how it should
be made or what such adjustment should be, but may accept as conclusive evidence
of the correctness of any such adjustment, and shall be protected in relying
upon the Officers' Certificate with respect thereto which the Company is
obligated to file with the Trustee pursuant to Section 5.11, 5.12 or 5.13.
Unless and until the Trustee receives any such Officers' Certificate, the
Trustee may assume without inquiry that none of the events described in Sections
5.11, 5.12 and 5.13 has occurred. The Trustee makes no representation as to the
validity or value of any securities or assets issued upon conversion of
Securities, and the Trustee shall not be responsible for the Company's failure
to comply with any provisions of this Article V.

      The Trustee shall not be under any responsibility to determine the
correctness of any provisions contained in any supplemental indenture executed
pursuant to Section 5.13, but may accept as conclusive evidence of the
correctness thereof, and shall be protected in relying upon, the

                                      -28-
<PAGE>
Officers' Certificate with respect thereto which the Company is obligated to
file with the Trustee pursuant to Section 5.13.

      SECTION 5.15 Automatic Conversion. The Company may elect to automatically
convert ("Automatic Conversion") the Securities on or prior to maturity if the
Daily Market Price of the Common Stock has exceeded 150% of the Conversion Price
for at least 20 Trading Days out of the 30 consecutive Trading Days ending
within five Trading Days prior to the date of (the "Notice Date") the notice of
automatic conversion (the "Automatic Conversion Notice").

      In order to effect an Automatic Conversion, the Company shall give to the
holder of each Security to be so converted an Automatic Conversion Notice. Such
Automatic Conversion Notice shall state:

            (i) the date on which the Securities identified in the Automatic
      Conversion Notice will be converted (the "Automatic Conversion Date");

            (ii) the CUSIP number or numbers of such Securities;

            (iii) the place or places where such Securities in certificated form
      are to be surrendered for exchange of the shares of Common Stock to be
      issued upon conversion thereof;

            (iv) the lowest Daily Market Price of the Common Stock for at least
      20 Trading Days out of the 30 consecutive Trading Days ending within five
      Trading Days prior to the giving of the Automatic Conversion Notice; and

            (v) the Conversion Price at which such Automatic Conversion is to be
      effected.

      If the Company elects to effect an Automatic Conversion Notice in respect
of fewer than all the Securities, the Automatic Conversion Notice relating to
such Automatic Conversion shall reference this Section 5.15 and shall identify
the Securities to be converted. In case any Security is to be converted in part
only, the Automatic Conversion Notice relating thereto shall state the portion
of the principal amount thereof to be converted and shall state that on and
after the date fixed for conversion, upon surrender of such Security, a new
Securities in principal amount equal to the portion thereof not converted will
be issued. In the case where the Company elects to effect an Automatic
Conversion in respect of any portion of the Security evidenced by the Global
Security, the beneficial interests in the Global Security to be subject to such
Automatic Conversion shall be selected by the Depositary in accordance with the
applicable standing procedures of the Depositary's book-entry conversion
program, and in connection with such Automatic Conversion the Depositary shall
arrange in accordance with such procedures for appropriate endorsements and
transfer documents, if required by the Company or the Trustee or conversion
agent, and payment of any transfer taxes if required hereunder.

      The Company or, at the request and expense of the Company, the Trustee
upon ten Business Days' notice prior to the date of the requested mailing (or
upon such shorter notice period as may be

                                      -29-
<PAGE>
reasonably acceptable to the Trustee), shall give to each holder of Securities
to be converted in an Automatic Conversion, at its last address as the same
shall appear on the Registrar, an Automatic Conversion Notice in respect
thereof. The date of Automatic Conversion of the Securities shall be not less
than 7 days nor more than 15 days from the Notice Date. Such Automatic
Conversion Notice shall be irrevocable and shall be mailed by first class mail
and, if mailed in the manner herein provided, shall be conclusively presumed to
have been given, whether or not the holder receives it. In any case, failure to
give such notice or any defect in the notice to the holder of any Security
designated for Automatic Conversion in whole or in part shall not affect the
validity of the proceedings for the Automatic Conversion of any such Security.
The Company shall also deliver a copy of each Automatic Conversion Notice given
by it to the Trustee.

                                   ARTICLE VI

                                  Subordination

      SECTION 6.01 Agreement to Subordinate. The Company, for itself and its
successors, and each Securityholder, by his acceptance of Securities, agree that
the payment of the principal of, premium, if any, or interest or any other
amounts due on the Securities is subordinated in right of payment, to the extent
and in the manner stated in this Article VI, to the prior payment in full of all
existing and future Senior Debt.

      SECTION 6.02 No Payment on Securities if Senior Debt in Default. Anything
in this Indenture to the contrary notwithstanding, no payment on account of
principal of, premium, if any, or interest, or any other amounts due on the
Securities (including, without limitation, any Designated Event Payments), and
no redemption, purchase, or other acquisition of the Securities (including,
without limitation, pursuant to a Designated Event Offer or Repurchase Offer),
shall be made by or on behalf of the Company (i) unless full payment of amounts
then due for principal and interest and of all other amounts then due on all
Senior Debt has been made or duly provided for pursuant to the terms of the
instrument governing such Senior Debt, (ii) if, at the time of such payment,
redemption, purchase or other acquisition, or immediately after giving effect
thereto, there shall exist under any Senior Debt, or any agreement pursuant to
which any Senior Debt is issued, any default, which default shall not have been
cured or waived and which default shall have resulted in the full amount of such
Senior Debt being declared due and payable or (iii) if, at the time of such
payment, redemption, purchase or other acquisition, the Trustee shall have
received written notice from the holders of Designated Senior Debt or a
Representative of such holders (a "Payment Blockage Notice") that there exists
under such Designated Senior Debt, or any agreement pursuant to which such
Designated Senior Debt is issued, any default, which default shall not have been
cured or waived, permitting the holders thereof to declare any amounts of such
Designated Senior Debt due and payable, but only for the period (the "Payment
Blockage Period") commencing on the date of receipt of the Payment Blockage
Notice and ending (unless earlier terminated by notice given to the Trustee by
the Representative of the holders of such Designated Senior Debt) on the earlier
of (a) the date on which such event of default shall have been cured or waived
or (b) 180 days from the receipt of the Payment Blockage Notice. Notwithstanding
the provisions described in the immediately preceding sentence (other than in
clauses (i) and (ii)), unless the holders of such Designated Senior

                                      -30-
<PAGE>
Debt or the Representative of such holders shall have accelerated the maturity
of such Designated Senior Debt, the Company may resume payments on the
Securities after the end of such Payment Blockage Period. Not more than one
Payment Blockage Notice may be given in any consecutive 360-day period,
irrespective of the number of defaults with respect to Senior Debt during such
period.

      In the event that, notwithstanding the provisions of this Section 6.02,
payments are made by or on behalf of the Company in contravention of the
provisions of this Section 6.02, such payments shall be held by the Trustee, any
Paying Agent or the holders, as applicable, in trust for the benefit of, and
shall be paid over to and delivered to the holders of Senior Debt or the
Representative under the indenture or other agreement (if any) pursuant to which
any instruments evidencing any Senior Debt may have been issued for application
to the payment of all Senior Debt ratably according to the aggregate amounts
remaining unpaid to the extent necessary to pay all Senior Debt in full in
accordance with the terms of such Senior Debt, after giving effect to any
concurrent payment or distribution to or for the holders of Senior Debt.

      The Company shall give prompt written notice to the Trustee and any Paying
Agent of any default or event of default under any Senior Debt or under any
agreement pursuant to which any Senior Debt may have been issued. The Trustee
and the Paying Agent may assume that all payments have been made with respect to
all Senior Debt unless the Trustee or the Paying Agent, as the case may be, has
received written notice that payment has not been made and three (3) Business
Days have expired.

      SECTION 6.03 Distribution on Acceleration of Securities; Dissolution and
Reorganization: Subrogation of Securities. (a) If the Securities are declared
due and payable because of the occurrence of an Event of Default, the Company
shall give prompt written notice to the holders of all Senior Debt or to the
trustee(s) for such Senior Debt of such acceleration. The Company may not pay
the principal of or interest or any other amounts due on the Securities until
five Business Days after such holders or trustee(s) of Senior Debt receive such
notice and, thereafter, the Company may pay the principal of or interest or any
other amounts due on the Securities only if the provisions of this Article VI
permit such payment.

      (b) Upon (i) any acceleration of the principal amount due on the
Securities because of an Event of Default or (ii) any direct or indirect
distribution of assets of the Company upon any dissolution, winding up,
liquidation or reorganization of the Company (whether in bankruptcy, insolvency
or receivership proceedings or upon an assignment for the benefit of creditors
or any other dissolution, winding up, liquidation or reorganization of the
Company):

                  (1) the holders of all Senior Debt shall first be entitled to
            receive payment in full of the principal thereof, the interest
            thereon and any other amounts due thereon before the holders are
            entitled to receive payment on account of the principal of or
            interest or any other amounts due on the Securities;

                  (2) any payment or distribution of assets of the Company of
            any kind or character, whether in cash, property or securities
            (other than securities of the Company as

                                      -31-
<PAGE>
            reorganized or readjusted or securities of the Company or any other
            corporation provided for by a plan of reorganization or readjustment
            the payment of which is subordinate, at least to the extent provided
            in this Article with respect to the Securities, to the payment in
            full without diminution or modification by such plan of all Senior
            Debt), to which the holders or the Trustee would be entitled except
            for the provisions of this Article, shall be paid by the liquidating
            trustee or agent or other person making such a payment or
            distribution, directly to the holders of Senior Debt (or
            Representative acting on their behalf), ratably according to the
            aggregate amounts remaining unpaid on account of the principal of or
            interest on and other amounts due on the Senior Debt held or
            represented by each, to the extent necessary to make payment in full
            of all Senior Debt remaining unpaid, after giving effect to any
            concurrent payment or distribution to the holders of such Senior
            Debt; and

                  (3) in the event that, notwithstanding the foregoing, any
            payment or distribution of assets of the Company of any kind or
            character, whether in cash, property or securities (other than
            securities of the Company as reorganized or readjusted, or
            securities of the Company or any other corporation provided for by a
            plan of reorganization or readjustment the payment of which is
            subordinate, at least to the extent provided in this Article with
            respect to the Securities, to the payment in full without diminution
            or modification by such plan of Senior Debt), shall be received by
            the Trustee or the holders before all Senior Debt is paid in full,
            such payment or distribution shall be held in trust for the benefit
            of, and be paid over to upon request by a holder of the Senior Debt,
            the holders of the Senior Debt remaining unpaid (or their
            Representative acting on their behalf), ratably as aforesaid, for
            application to the payment of such Senior Debt until all such Senior
            Debt shall have been paid in full, after giving effect to any
            concurrent payment or distribution to the holders of such Senior
            Debt.

      Subject to the payment in full of all Senior Debt, the holders shall be
subrogated to the rights of the holders of Senior Debt to receive payments or
distributions of cash, property or securities of the Company applicable to the
Senior Debt until the principal of and interest shall be paid in full and, for
purposes of such subrogation, no such payments or distributions to the holders
of Senior Debt of cash, property or securities which otherwise would have been
payable or distributable to holders shall, as among the Company, its creditors
other than the holders of Senior Debt, and the holders, be deemed to be a
payment by the Company to or on account of the Senior Debt, it being understood
that the provisions of this Article are and are intended solely for the purpose
of defining the relative rights of the holders, on the one hand, and the holders
of Senior Debt, on the other hand.

      Nothing contained in this Article or elsewhere in this Indenture or in the
Securities is intended to or shall (i) impair, as between the Company and its
creditors other than the holders of Senior Debt, the obligation of the Company,
which is absolute and unconditional, to pay to the holders the principal of, and
interest as and when the same shall become due and payable in accordance with
the terms of the Securities, (ii) affect the relative rights of the holders and
creditors of the Company other than holders of Senior Debt or, as between the
Company and the Trustee, the obligations of the Company to the Trustee, or (iii)
prevent the Trustee or the holders from exercising all remedies otherwise
permitted by applicable law upon default under this Indenture, subject to the

                                      -32-
<PAGE>
rights, if any, under this Article of the holders of Senior Debt in respect of
cash, property and securities of the Company received upon the exercise of any
such remedy.

         Upon distribution of assets of the Company referred to in this Article,
the Trustee, subject to the provisions of Section 9.01 hereof, and the holders
shall be entitled to rely upon a certificate of the liquidating trustee or agent
or other person making any distribution to the Trustee or to the holders for the
purpose of ascertaining the persons entitled to participate in such
distribution, the holders of the Senior Debt and other indebtedness of the
Company, the amount thereof or payable thereon, the amount or amounts paid or
distributed thereon and all other facts pertinent thereto or to this Article.
The Trustee, however, shall not be deemed to owe any fiduciary duty to the
holders of Senior Debt. Nothing contained in this Article or elsewhere in this
Indenture, or in any of the Securities, shall prevent the good faith application
by the Trustee of any moneys which were deposited with it hereunder, prior to
its receipt of written notice of facts which would prohibit such application,
for the purpose of the payment of or on account of the principal of, or interest
unless, prior to the date on which such application is made by the Trustee, the
Trustee shall be charged with actual notice under Section 6.03(d) hereof of the
facts which would prohibit the making of such application.

      (c) The provisions of this Article shall not be applicable to any cash,
properties or securities received by the Trustee or by any holder when received
as a holder of Senior Debt and nothing in Section 9.11 hereof or elsewhere in
this Indenture shall deprive the Trustee or such holder of any of its rights as
such holder of Senior Debt.

      (d) The Company shall give prompt written notice to the Trustee of any
fact known to the Company which would prohibit the making of any payment of
money to or by the Trustee in respect of the Securities pursuant to the
provisions of this Article. The Trustee, subject to the provisions of Section
9.01 hereof, shall be entitled to assume that no such fact exists unless the
Company or any holder of Senior Debt or any Representative therefor has given
written notice thereof to the Trustee. Notwithstanding the provisions of this
Article or any other provisions of this Indenture, the Trustee shall not be
charged with knowledge of the existence of any fact which would prohibit the
making of any payment of moneys to or by the Trustee in respect of the
Securities pursuant to the provisions in this Article, unless, and until three
Business Days after, the Trustee shall have received written notice thereof from
the Company or any holder or holders of Senior Debt or from any Representative
therefor; and, prior to the receipt of any such written notice, the Trustee,
subject to the provisions of Section 9.01 hereof, shall be entitled in all
respects conclusively to assume that no such facts exist; provided that if on a
date not less than three Business Days immediately preceding the date upon
which, by the terms hereof, any such moneys may become payable for any purpose
(including, without limitation, the principal of or interest), the Trustee shall
not have received with respect to such moneys the notice provided for in this
Section 6.03(d), then anything herein contained to the contrary notwithstanding,
the Trustee shall have full power and authority to receive such moneys and to
apply the same to the purpose for which they were received, and shall not be
affected by any notice to the contrary which may be received by it on or after
such prior date.

                                      -33-
<PAGE>
         The Trustee shall be entitled to conclusively rely on the delivery to
it of a written notice by a person representing himself to be a holder of Senior
Debt (or a Representative on behalf of such holder) to establish that such
notice has been given by a holder of Senior Debt (or a Representative on behalf
of any such holder or holders). In the event that the Trustee determines in good
faith that further evidence is required with respect to the right of any person
as a holder of Senior Debt to participate in any payment or distribution
pursuant to this Article, the Trustee may request such person to furnish
evidence to the reasonable satisfaction of the Trustee as to the amount of
Senior Debt held by such person, the extent to which such person is entitled to
participate in such payment or distribution and any other facts pertinent to the
rights of such person under this Article, and, if such evidence is not
furnished, the Trustee may defer any payment to such person pending judicial
determination as to the right of such person to receive such payment; nor shall
the Trustee be charged with knowledge or the curing or waiving of any default of
the character specified in Section 6.02 hereof or that any event or any
condition preventing any payment in respect of the Securities shall have ceased
to exist, unless and until the Trustee shall have received written notice to
such effect.

      (e) The provisions of this Section 6.03 applicable to the Trustee shall
(unless the context requires otherwise) also apply to any Paying Agent for the
Company.

      SECTION 6.04 Reliance by Holders of Senior Debt on Subordination
Provisions. Each holder of any Security by his acceptance thereof acknowledges
and agrees that the foregoing subordination provisions are, and are intended to
be, an inducement and a consideration for each holder of any Senior Debt,
whether such Senior Debt was created or acquired before or after the issuance of
the Securities, to acquire and continue to hold, or to continue to hold, such
Senior Debt, and such holder of Senior Debt shall be deemed conclusively to have
relied on such subordination provisions in acquiring and continuing to hold, or
in continuing to hold, such Senior Debt. Notice of any default in the payment of
any Senior Debt, except as expressly stated in this Article, and notice of
acceptance of the provisions hereof are hereby expressly waived. Except as
otherwise expressly provided herein, no waiver, forbearance or release by any
holder of Senior Debt under such Senior Debt or under this Article shall
constitute a release of any of the obligations or liabilities of the Trustee or
holders of the Securities provided in this Article.

      SECTION 6.05 No Waiver of Subordination Provisions. Except as
otherwise expressly provided herein, no right of any present or future holder of
any Senior Debt to enforce subordination as herein provided shall at any time in
any way be prejudiced or impaired by any act or failure to act on the part of
the Company or by any act or failure to act, in good faith, by any such holder,
or by any noncompliance by the Company with the terms, provisions and covenants
of this Indenture, regardless of any knowledge thereof any such holder may have
or be otherwise charged with.

      Without in any way limiting the generality of the foregoing paragraph, the
holders of Senior Debt may, at any time and from time to time, without the
consent of, or notice to, the Trustee or the holders of the Securities, without
incurring responsibility to the holders of the Securities and without impairing
or releasing the subordination provided in this Article VI or the obligations
hereunder of the holders of the Securities to the holders of Senior Debt, do any
one or more of the following:

                                      -34-

<PAGE>
(i) change the manner, place or terms of payment of, or renew or alter, Senior
Debt, or otherwise amend or supplement in any manner Senior Debt or any
instrument evidencing the same or any agreement under which Senior Debt is
outstanding; (ii) sell, exchange, release or otherwise dispose of any property
pledged, mortgaged or otherwise securing Senior Debt; (iii) release any person
liable in any manner for the collection of Senior Debt; and (iv) exercise or
refrain from exercising any rights against the Company or any other person.

      SECTION 6.06      Trustee's Relation to Senior Debt. The Trustee in its
individual capacity shall be entitled to all the rights set forth in this
Article in respect of any Senior Debt at any time held by it, to the same extent
as any holder of Senior Debt, and nothing in Section 9.11 hereof or elsewhere in
this Indenture shall deprive the Trustee of any of its rights as such holder.

      With respect to the holders of Senior Debt, the Trustee undertakes to
perform or to observe only such of its covenants and obligations, as are
specifically set forth in this Article, and no implied covenants or obligations
with respect to the holders of Senior Debt shall be read into this Indenture
against the Trustee. The Trustee shall not owe any fiduciary duty to the holders
of Senior Debt but shall have only such obligations to such holders as are
expressly set forth in this Article.

      Each holder of a Security by his acceptance thereof authorizes and directs
the Trustee on his behalf to take such action as may be necessary or appropriate
to effectuate the subordination provided in this Article and appoints the
Trustee his attorney-in-fact for any and all such purposes, including, in the
event of any dissolution, winding up or liquidation or reorganization under any
applicable bankruptcy law of the Company (whether in bankruptcy, insolvency or
receivership proceedings or otherwise), the timely filing of a claim for the
unpaid balance of such holder's Securities in the form required in such
proceedings and the causing of such claim to be approved. If the Trustee does
not file a claim or proof of debt in the form required in such proceedings prior
to 30 days before the expiration of the time to file such claims or proofs, then
any holder or holders of Senior Debt or their Representative or Representatives
shall have the right to demand, sue for, collect, receive and receipt for the
payments and distributions in respect of the Securities which are required to be
paid or delivered to the holders of Senior Debt as provided in this Article and
to file and prove all claims therefor and to take all such other action in the
name of the holders or otherwise, as such holders of Senior Debt or
Representative thereof may determine to be necessary or appropriate for the
enforcement of the provisions of this Article.

      SECTION 6.07      Other Provisions Subject Hereto. Except as expressly
stated in this Article, notwithstanding anything contained in this Indenture to
the contrary, all the provisions of this Indenture and the Securities are
subject to the provisions of this Article. However, nothing in this Article
shall apply to or adversely affect the claims of, or payment to, the Trustee
pursuant to Section 9.07. Notwithstanding the foregoing, the failure to make a
payment on account of principal of or interest by reason of any provision of
this Article VI shall not be construed as preventing the occurrence of an Event
of Default under Section 8.01.

      SECTION 6.08      Certain Conversions and Repurchases Deemed Payment. For
the purposes of this Article only, (i) the issuance and delivery of junior
securities upon conversion of Securities in accordance with Article V shall not
be deemed to constitute a payment or distribution

                                      -35-
<PAGE>
on account of the principal of or premium or interest or on account of the
purchase or other acquisition of Securities, and (ii) the payment, issuance or
delivery of cash (except in satisfaction of fractional shares pursuant to
Section 5.03), property or securities (other than junior securities) upon
conversion of a Security shall be deemed to constitute payment on account of the
principal of such Security. For the purposes of this Section, the term "junior
securities" means (a) shares of any stock of any class of the Company and
securities into which the Securities are convertible pursuant to Article V and
(b) securities of the Company which are subordinated in right of payment to all
Senior Debt which may be outstanding at the time of issuance or delivery of such
securities to substantially the same extent as, or to a greater extent than, the
Securities are so subordinated as provided in this Article. Nothing contained in
this Article or elsewhere in this Indenture or in the Securities is intended to
or shall impair, as among the Company, its creditors other than holders of
Senior Debt and the holders of the Securities, the right, which is absolute and
unconditional, of the holder of any Security to convert such Security in
accordance with Article V.

                                  ARTICLE VII

                                   Successors

      SECTION 7.01      Merger, Consolidation or Sale of Assets. The Company may
not consolidate or merge with or into any person (whether or not the Company is
the surviving entity), or sell, assign, transfer, lease, convey or otherwise
dispose of all or substantially all of its properties or assets unless:

            (a)   the Company is the surviving Corporate Entity or the Corporate
Entity formed by or surviving any such consolidation or merger (if other than
the Company) or to which such sale, assignment, transfer, lease, conveyance or
other disposition shall have been made is a Corporate Entity organized or
existing under the laws of the United States, any state thereof or the District
of Columbia;

            (b)   the Corporate Entity formed by or surviving any such
consolidation or merger (if other than the Company) or the Corporate Entity to
which such sale, assignment, transfer, lease, conveyance or other disposition
will have been made assumes all the Obligations of the Company, pursuant to a
supplemental indenture in a form reasonably satisfactory to the Trustee, under
the Securities and the Indenture;

            (c)   immediately after such transaction no Default or Event of
Default exists; and

            (d)   the Company or such person shall have delivered to the Trustee
an Officers' Certificate and an Opinion of Counsel, each stating that such
transaction and the supplemental indenture comply with the Indenture and that
all conditions precedent in the Indenture relating to such transaction have been
satisfied.

      SECTION 7.02      Successor Corporate Entity Substituted. Upon any
consolidation or merger, or any sale, assignment, transfer, lease, conveyance or
other disposition of all or substantially all of the assets of the Company in
accordance with Section 7.01 hereof, the successor

                                      -36-
<PAGE>
Corporate Entity formed by such consolidation or into or with which the Company
is merged or the person to which such sale, assignment, transfer, lease,
conveyance or other disposition is made shall succeed to, and be substituted for
and may exercise every right and power of, the Company under this Indenture with
the same effect as if such successor Corporate Entity has been named as the
Company herein; provided, however, that the predecessor Company in the case of a
sale, assignment, transfer, lease, conveyance or other disposition shall not be
released from the obligation to pay the principal of and interest.

                                  ARTICLE VIII

                              Defaults and Remedies

      SECTION 8.01      Events of Default. An "Event of Default" occurs if:

            (a)   the Company defaults in the payment of interest when the same
becomes due and payable, and the Default continues for a period of 30 days after
the date due and payable;

            (b)   the Company defaults in the payment of the principal of any
Security when the same becomes due and payable at maturity, upon redemption or
otherwise;

            (c)   the Company defaults in the payment of the Designated Event
Payment when the same becomes due and payable, whether or not such payment may
be prohibited by Article VI;

            (d)   the Company fails to provide timely notice of any Designated
Event in accordance with Section 4.08;

            (e)   the Company fails to observe or perform any other covenant or
agreement contained in this Indenture or the Securities required by it to be
performed and the Default continues for a period of 60 days after the receipt of
written notice from the Trustee to the Company or from the holders of 25% in
aggregate principal amount of the then outstanding Securities to the Company and
the Trustee stating that such notice is a "Notice of Default";

            (f)   there is a default under any mortgage, indenture or instrument
under which there may be issued or by which there may be secured or evidenced
any Indebtedness for money borrowed by the Company or any Subsidiary of the
Company (or the payment of which is guaranteed by the Company or any Subsidiary
of the Company), whether such Indebtedness or guarantee now exists or is created
after the Issuance Date, which default (i) is caused by a failure to pay when
due principal of or interest on such Indebtedness within the grace period
provided for in such Indebtedness (which failure continues beyond any applicable
grace period) (a "Payment Default") or (ii) results in the acceleration of such
Indebtedness prior to its express maturity (without such acceleration being
rescinded or annulled) and, in each case, the principal amount of any such
Indebtedness, together with the principal amount of any other such Indebtedness
under which there is a Payment Default or the maturity of which has been so
accelerated, aggregates $10 million or more;

                                      -37-
<PAGE>
            (g)   a final non-appealable judgment or final non-appealable
judgments (other than any judgment as to which a reputable insurance company has
accepted full liability) for the payment of money are entered by a court or
courts of competent jurisdiction against the Company or any Subsidiary of the
Company and remain undischarged for a period (during which execution shall not
be effectively stayed) of 60 days, provided that the aggregate of all such
judgments exceeds $10 million;

            (h)   the Company or any Material Subsidiary pursuant to or within
the meaning of any Bankruptcy Law: (i) commences a voluntary case, (ii) consents
to the entry of an order for relief against it in an involuntary case in which
it is the debtor, (iii) consents to the appointment of a Bankruptcy Custodian of
it or for all or substantially all of its property, (iv) makes a general
assignment for the benefit of its creditors, or (v) makes the admission in
writing that it generally is unable to pay its debts as the same become due; or

            (i)   a court of competent jurisdiction enters an order or decree
under any Bankruptcy Law that: (i) is for relief against the Company or any
Material Subsidiary in an involuntary case, (ii) appoints a Bankruptcy Custodian
of the Company or any Material Subsidiary or for all or substantially all of its
property, and the order or decree remains unstayed and in effect for 60 days or
(iii) orders the liquidation of the Company or any Material Subsidiary, and the
order or decree remains unstayed and in effect for 60 days.

      The term "Bankruptcy Law" means Title 11, U.S. Code or any similar Federal
or state law for the relief of debtors. The term "Bankruptcy Custodian" means
any receiver, trustee, assignee, liquidator or similar official under any
Bankruptcy Law.

      SECTION 8.02      Acceleration. If an Event of Default (other than an
Event of Default specified in clauses (h) and (i) of Section 8.01 hereof with
respect to the Company) occurs and is continuing, the Trustee by notice to the
Company, or the Securityholders of at least 25% in principal amount of the
then-outstanding Securities by notice to the Company and the Trustee, may
declare all the Securities to be due and payable. Upon such declaration, the
principal of, premium, if any, and accrued and unpaid interest shall be due and
payable immediately. If an Event of Default specified in clause (h) or (i) of
Section 8.01 hereof occurs with respect to the Company, such an amount shall
ipso facto become and be immediately due and payable without any declaration or
other act on the part of the Trustee or any Securityholder. The Securityholders
of a majority in aggregate principal amount of the then-outstanding Securities
by notice to the Trustee may rescind an acceleration and its consequences if the
rescission would not conflict with any judgment or decree, if all amounts
payable to the Trustee pursuant to Section 9.07 hereof have been paid and if all
existing Events of Default have been cured or waived except nonpayment of
principal or interest that has become due solely because of the acceleration.

      SECTION 8.03      Other Remedies. If an Event of Default occurs and is
continuing, the Trustee may pursue any available remedy to collect the payment
of principal or interest or to enforce the performance of any provision of the
Securities or this Indenture.

                                      -38-
<PAGE>
      The Trustee may maintain a proceeding even if it does not possess any of
the Securities or does not produce any of them in the proceeding. A delay or
omission by the Trustee or any Securityholder in exercising any right or remedy
accruing upon an Event of Default shall not impair the right or remedy or
constitute a waiver of or acquiescence in the Event of Default. All remedies are
cumulative to the extent permitted by law.

      SECTION 8.04      Waiver of Past Defaults. The Securityholders of a
majority in aggregate principal amount of the then-outstanding Securities by
notice to the Trustee may waive an existing Default or Event of Default and its
consequences except a continuing Default or Event of Default in the payment of
the Designated Event Payment or the principal of, or interest. When a Default or
Event of Default is waived, it is cured and ceases; but no such waiver shall
extend to any subsequent or other Default or impair any right consequent
thereon.

      SECTION 8.05      Control by Majority. The Securityholders of a majority
in principal amount of the then-outstanding Securities may direct the time,
method and place of conducting any proceeding for any remedy available to the
Trustee or exercising any trust or power conferred on it. However, the Trustee
may refuse to follow any direction that conflicts with law or this Indenture, is
unduly prejudicial to the rights of other Securityholders, or would involve the
Trustee in personal liability.

      SECTION 8.06      Limitation on Suits. A Securityholder may pursue a
remedy with respect to this Indenture or the Securities only if:

            (a)   the Securityholder gives to the Trustee notice of a continuing
Event of Default;

            (b)   the Securityholders of at least 25% in principal amount of the
then-outstanding Securities make a request to the Trustee to pursue the remedy;

            (c)   such Securityholder or Securityholders offer to the Trustee
indemnity satisfactory to the Trustee against any loss, liability or expense;

            (d)   the Trustee does not comply with the request within 60 days
after receipt of the request and the offer of indemnity; and

            (e)   during such 60-day period the Securityholders of a majority in
principal amount of the then-outstanding Securities do not give the Trustee a
direction inconsistent with the request.

      A Securityholder may not use this Indenture to prejudice the rights of
another Securityholder or to obtain a preference or priority over another
Securityholder.

      SECTION 8.07      Rights of Securityholders to Receive Payment.
Notwithstanding any other provision of this Indenture, the right of any
Securityholder of a Security to receive payment of principal and interest on or
after the respective due dates expressed in the Security, or to bring suit for
the enforcement of any such payment on or after such respective dates, shall not
be impaired or affected without the consent of the Securityholder made pursuant
to this Section.

                                      -39-
<PAGE>
      SECTION 8.08      Collection Suit by Trustee. If an Event of Default
specified in Section 8.01 (a), (b) or (c) occurs and is continuing, the Trustee
may recover judgment in its own name and as trustee of an express trust against
the Company for the whole amount of principal and interest and such further
amount as shall be sufficient to cover the costs and, to the extent lawful,
expenses of collection, including the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel.

      SECTION 8.09      Trustee May File Proofs of Claim. The Trustee may file
such proofs of claim and other papers or documents as may be necessary or
advisable in order to have the claims of the Trustee and the Securityholders
allowed in any judicial proceedings relative to the Company, its creditors or
its property. Nothing contained herein shall be deemed to authorize the Trustee
to authorize or consent to or accept or adopt on behalf of any Securityholder
any plan of reorganization, arrangement, adjustment or composition affecting the
Securities or the rights of any Securityholder thereof, or to authorize the
Trustee to vote in respect of the claim of any Securityholder in any such
proceeding.

      SECTION 8.10      Priorities. If the Trustee collects any money pursuant
to this Article, it shall pay out the money in the following order:

      First: to the Trustee for amounts due under Section 9.07 hereof;

      Second: to the holders of Senior Debt to the extent required by Article
VI;

      Third: to the Securityholders, for amounts due and unpaid on the
Securities for principal and interest, ratably, according to the amounts due and
payable on the Securities for principal and interest, respectively; and

      Fourth: to the Company.

      Except as otherwise provided in Section 2.12 hereof, the Trustee may fix a
record date and payment date for any payment to Securityholders made pursuant to
this Section.

      SECTION 8.11      Undertaking for Costs. In any suit for the enforcement
of any right or remedy under this Indenture or in any suit against the Trustee
for any action taken or omitted by it as a Trustee, a court in its discretion
may require the filing by any party litigant in the suit of an undertaking to
pay the costs of the suit, and the court in its discretion may assess reasonable
costs, including reasonable attorneys' fees, against any party litigant in the
suit, having due regard to the merits and good faith of the claims or defenses
made by the party litigant. This Section does not apply to a suit by the
Trustee, a suit by a holder pursuant to Section 8.07 hereof, or a suit by
Securityholders of more than 10% in principal amount of the then-outstanding
Securities.

                                   ARTICLE IX

                                     Trustee

                                      -40-
<PAGE>
      SECTION 9.01      Duties of Trustee.

            (a)   If an Event of Default has occurred and is continuing, the
Trustee shall exercise such of the rights and powers vested in it by this
Indenture, and use the same degree of care and skill in their exercise, as a
prudent man would exercise or use under the circumstances in the conduct of his
own affairs.

            (b)   Except during the continuance of an Event of Default: (i) the
Trustee need perform only those duties that are specifically set forth in this
Indenture and no others and (ii) in the absence of bad faith on its part, the
Trustee may conclusively rely, as to the truth of the statements and the
correctness of the opinions expressed therein, upon certificates or opinions
furnished to the Trustee and, if required by the terms hereof, conforming to the
requirements of this Indenture. However, the Trustee shall examine the
certificates and opinions to determine whether or not they conform to the
requirements of this Indenture.

            (c)   The Trustee may not be relieved from liability for its own
negligent action, its own negligent failure to act, or its own willful
misconduct, except that: (i) this paragraph does not limit the effect of
paragraph (b) of this Section 9.01; (ii) the Trustee shall not be liable for any
error of judgment made in good faith by a Trust Officer, unless it is proved
that the Trustee was negligent in ascertaining the pertinent facts and (iii) the
Trustee shall not be liable with respect to any action it takes or omits to take
in good faith in accordance with a direction received by it pursuant to Section
8.05 hereof.

            (d)   Every provision of this Indenture that in any way relates to
the Trustee is subject to paragraphs (a), (b) and (c) of this Section 9.01. No
provision of this Indenture shall require the Trustee to expend or risk its own
funds or otherwise incur any financial liability in the performance of any of
its duties hereunder, or in the exercise of any of its rights or powers, if it
shall have reasonable grounds for believing that repayment of such funds or
adequate indemnity against such risk or liability is not reasonably assured to
it.

            (e)   The Trustee may refuse to perform any duty or exercise any
right or power unless it receives indemnity satisfactory to it against any loss,
liability or expense.

            (f)   The Trustee shall not be liable for interest on any money
received by it except as the Trustee may agree in writing with the Company.
Money held in trust by the Trustee need not be segregated from other funds
except to the extent required by law.

      SECTION 9.02      Rights of Trustee.

            (a)   The Trustee may rely on any document believed by it to be
genuine and to have been signed or presented by the proper person. The Trustee
need not investigate any fact or matter stated in the document.

            (b)   Before the Trustee acts or refrains from acting, it (unless
other evidence be herein specifically prescribed) may require an Officers'
Certificate or an Opinion of Counsel, or both. The

                                      -41-
<PAGE>
Trustee shall not be liable for any action it takes or omits to take in good
faith in reliance on such Officers' Certificate or Opinion of Counsel.

            (c)   The Trustee may act through agents and nominees and shall not
be responsible for the misconduct or negligence of any agent appointed with due
care.

            (d)   The Trustee shall not be liable for any action it takes or
omits to take in good faith which it believes to be authorized or within its
rights or powers.

            (e)   The Trustee shall not be charged with knowledge of any Event
of Default under subsection (d), (e), (f), (g), (h) or (i) of Section 8.01
unless either (1) a Trust Officer assigned to its Corporate Trust Department
shall have actual knowledge thereof, or (2) the Trustee shall have received
notice thereof in accordance with Section 12.02 hereof from the Company or any
holder.

      SECTION 9.03      Individual Rights of Trustee. The Trustee in its
individual or any other capacity may become the owner or pledgee of Securities
and may otherwise deal with the Company or an Affiliate with the same rights it
would have if it were not Trustee. Any Agent may do the same with like rights.
However, the Trustee is subject to Sections 9.10 and 9.11 hereof.

      SECTION 9.04      Trustee's Disclaimer. The Trustee makes no
representation as to the validity or adequacy of this Indenture or the
Securities, it shall not be accountable for the Company's use of the proceeds
from the Securities, and it shall not be responsible for any statement of the
Company in the Indenture or any statement in the Securities other than its
authentication.

      SECTION 9.05      Notice of Defaults. If a Default or Event of Default
occurs and is continuing and if it is known to the Trustee, the Trustee shall
mail to Securityholders a notice of the Default or Event of Default within 90
days after it occurs. Except in the case of a Default or Event of Default in
payment on any Security, the Trustee may withhold the notice if and so long as a
committee of its Trust Officers in good faith determines that withholding the
notice is in the interests of Securityholders.

      SECTION 9.06      Reports by Trustee to Securityholders. Within 60 days
after the reporting date stated in Section 12.10, the Trustee shall mail to
Securityholders a brief report dated as of such reporting date that complies
with TIA Section 313(a) if and to the extent required by such Section 313(a).
The Trustee also shall comply with TIA Section 313(b)(2). The Trustee shall also
transmit by mail all reports as required by TIA Section 313(c).

      A copy of each report at the time of its mailing to Securityholders shall
be filed with the SEC and each stock exchange on which the Securities are
listed. The Company shall notify the Trustee when the Securities are listed on
any stock exchange or automated quotation system.

      SECTION 9.07      Compensation and Indemnity. The Company shall pay to the
Trustee from time to time reasonable compensation for its services hereunder.
The Trustee's compensation shall not be limited by any law on compensation of a
trustee of an express trust. The Company shall reimburse the Trustee upon
request for all reasonable disbursements, expenses and advances

                                      -42-
<PAGE>
incurred or made by it. Such disbursements and expenses may include the
reasonable disbursements, compensation and expenses of the Trustee's agents and
counsel.

      The Company shall indemnify the Trustee and its officers, directors,
employees and agents against any loss or liability incurred by it except as set
forth in the next paragraph. The Trustee shall notify the Company promptly of
any claim for which it may seek indemnity. The Company shall defend the claim
and the Trustee shall cooperate in the defense. The Trustee may have separate
counsel and the Company shall pay the reasonable fees, disbursements and
expenses of such counsel. The Company need not pay for any settlement made
without its consent, which consent shall not be unreasonably withheld.

      The Company need not reimburse any expense or indemnify against any loss
or liability incurred by the Trustee through negligence, bad faith or willful
misconduct.

      To secure the Company's payment obligations in this Section, the Trustee
shall have a lien prior to the Securities on all money or property held or
collected by the Trustee, except money or property held in trust to pay
principal and interest.

      When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 8.01(h) or (i) occurs, the expenses and the
compensation for the services are intended to constitute expenses of
administration under any Bankruptcy Law.

      The provisions of this Section 9.07 shall survive the termination of this
Indenture, as provided by Section 10.01 hereof.

      SECTION 9.08      Replacement of Trustee. A resignation or removal of the
Trustee and appointment of a successor Trustee shall become effective only upon
the successor Trustee's acceptance of appointment as provided in this Section.

      The Trustee may resign by so notifying the Company. The Securityholders of
a majority in principal amount of the then-outstanding Securities may remove the
Trustee by so notifying the Trustee and the Company. The Company may remove the
Trustee if:

            (a)   the Trustee fails to comply with Section 9.10 hereof, unless
the Trustee's duty to resign is stayed as provided in TIA Section 310(b);

            (b)   the Trustee is adjudged a bankrupt or an insolvent or an order
for relief is entered with respect to the Trustee under any Bankruptcy Law;

            (c)   a Bankruptcy Custodian or public officer takes charge of the
Trustee or its property, or

            (d)   the Trustee becomes incapable of acting.

                                      -43-
<PAGE>
      If the Trustee resigns or is removed or if a vacancy exists in the office
of Trustee for any reason, the Company shall promptly appoint a successor
Trustee. Within one year after the successor Trustee takes office, the
Securityholders of a majority in principal amount of the then-outstanding
Securities may appoint a successor Trustee to replace the successor Trustee
appointed by the Company.

      If a successor Trustee does not take office within 60 days after the
retiring Trustee resigns or is removed, the retiring Trustee, the Company or the
Securityholders of at least 10% in principal amount of the then-outstanding
Securities may petition any court of competent jurisdiction for the appointment
of a successor Trustee.

      If the Trustee fails to comply with Section 9.10 hereof, unless the
Trustee's duty to resign is stayed as provided in TIA Section 310(b), any
Securityholder who has been a bona fide holder of a Security for at least six
months may petition any court of competent jurisdiction for the removal of the
Trustee and the appointment of a successor Trustee.

      A successor Trustee shall deliver a written acceptance of its appointment
to the retiring Trustee and to the Company. Thereupon the resignation or removal
of the retiring Trustee shall become effective, the Company shall promptly pay
all amounts due and payable to the retiring Trustee, and the successor Trustee
shall have all the rights, powers and duties of the Trustee under this
Indenture. The successor Trustee shall mail a notice of its succession to
Securityholders. The retiring Trustee shall promptly transfer all property held
by it as Trustee to the successor Trustee, subject to the lien provided for in
Section 9.07 hereof. Notwithstanding the resignation or replacement of the
Trustee pursuant to this Section 9.08, the Company's obligations under Section
9.07 hereof shall continue for the benefit of the retiring Trustee with respect
to expenses and liabilities incurred by it prior to such resignation or
replacement.

      SECTION 9.09      Successor Trustee by Merger, Etc. If the Trustee
consolidates, merges or converts into, or transfers all or substantially all of
its corporate trust business (including the administration of the Indenture) to,
another corporation, the successor corporation without any further act shall be
the successor Trustee.

      SECTION 9.10      Eligibility; Disqualification. This Indenture shall
always have a Trustee who satisfies the requirements of TIA Section 310(a)(1)
and (5). The Trustee (or if the Trustee is a member of a bank holding system,
its bank holding company) shall always have a combined capital and surplus as
stated in Section 12.10 hereof. The Trustee is subject to TIA Section 310(b).

      SECTION 9.11      Preferential Collection of Claims Against Company. The
Trustee is subject to TIA Section 311(a), excluding any credit or relationship
listed in TIA Section 311(b). A Trustee who has resigned or been removed shall
be subject to TIA Section 311(a) to the extent indicated therein.

      SECTION 9.12      Sections Applicable to Registrar, Paying Agent and
Conversion Agent.

      The term "Trustee" as used in Sections 6.3, 9.1, 9.2, 9.3, 9.4 and 9.7
hereof shall (unless the

                                      -44-
<PAGE>
context requires otherwise) be construed as extending to and including the
Trustee acting in its capacity, if any, as Registrar, Paying Agent and
Conversion Agent.

                                    ARTICLE X

                             Discharge of Indenture

      SECTION 10.01     Termination of Company's Obligation. This Indenture
shall cease to be of further effect (except that the Company's obligations under
Sections 9.07 and 10.02 hereof shall survive) when all outstanding Securities
theretofore authenticated and issued have been delivered to the Trustee for
cancellation and the Company has paid all sums payable hereunder.

      Thereupon, the Trustee upon request of the Company, shall acknowledge in
writing the discharge of the Company's obligations under this Indenture, except
for those surviving obligations specified above.

      SECTION 10.02     Repayment to Company. The Trustee and the Paying Agent
shall promptly pay to the Company upon request any excess money or securities
held by them at any time.

      The Trustee and the Paying Agent shall pay to the Company upon request any
money held by them for the payment of principal or interest that remains
unclaimed for two years after the date upon which such payment shall have become
due; provided, however, that the Company shall have first caused notice of such
payment to the Company to be mailed to each Securityholder entitled thereto no
less than 30 days prior to such payment. After payment to the Company, the
Trustee and the Paying Agent shall have no further liability with respect to
such money and Securityholders entitled to the money must look to the Company
for payment as general creditors unless any applicable abandoned property law
designates another person.

                                   ARTICLE XI

                       Amendments, Supplements and Waivers

      SECTION 11.01     Without Consent of Securityholders. The Company and the
Trustee may amend or supplement this Indenture or the Securities without the
consent of any Securityholder:

            (a)   to cure any ambiguity, defect or inconsistency;

            (b)   to comply with Sections 5.13 and 7.01 hereof;

            (c)   to provide for uncertificated Securities in addition to
certificated Securities;

            (d)   to make any change that does not adversely affect the legal
rights hereunder of any Securityholder;

                                      -45-
<PAGE>
            (e)   to qualify this Indenture under the TIA or to comply with the
requirements of the SEC in order to maintain the qualification of the Indenture
under the TIA; or

            (f)   to make any change that provides any additional rights or
benefits to the holders of Securities.

      An amendment under this Section may not make any change that adversely
affects the rights under Article VI of any holder of Senior Debt then
outstanding unless the holders of such Senior Debt (or any group or
Representative thereof authorized to give a consent) consent to such change.

      SECTION 11.02     With Consent of Securityholders. Subject to Section 8.07
hereof, the Company and the Trustee may amend or supplement this Indenture or
the Securities with the written consent (including consents obtained in
connection with any tender or exchange offer for Securities) of the
Securityholders of at least a majority in principal amount of the
then-outstanding Securities. Subject to Sections 8.04 and 8.07 hereof, the
Securityholders of a majority in principal amount of the Securities then
outstanding may also by their written consent (including consents obtained in
connection with any tender offer or exchange offer for Securities) waive any
existing Default as provided in Section 8.04 or waive compliance in a particular
instance by the Company with any provision of this Indenture or the Securities.
However, without the consent of each Securityholder affected, an amendment,
supplement or waiver under this Section may not (with respect to any Securities
held by a nonconsenting Securityholder):

            (a)   reduce the amount of Securities whose Securityholders must
consent to an amendment, supplement or waiver;

            (b)   reduce the rate of or change the time for payment of interest
on any Security;

            (c)   reduce the principal of or change the fixed maturity of any
Security or alter the redemption provisions with respect thereto;

            (d)   make any Security payable in money other than that stated in
the Security;

            (e)   make any change in Section 8.04, 8.07 or 11.02 hereof (this
sentence);

            (f)   waive a default in the payment of principal of, premium, if
any, or interest (other than as provided in Section 8.04);

            (g)   waive a redemption payment payable on any Security;

            (h)   make any change that impairs the right of Securityholders to
convert Securities into Common Stock of the Company; or

            (i)   modify the conversion or subordination provisions set forth in
Article V and Article VI, respectively, in a manner adverse to the holders of
the Securities.

                                      -46-
<PAGE>
      To secure a consent of the Securityholders under this Section 11.02, it
shall not be necessary for the Securityholders to approve the particular form of
any proposed amendment, supplement or waiver, but it shall be sufficient if such
consent approves the substance thereof.

      An amendment under this Section may not make any change that adversely
affects the rights under Article VI of any holder of Senior Debt then
outstanding unless the holders of such Senior Debt (or any group or
Representative thereof authorized to give a consent) consent to such change.

      Neither the Company nor any of its Subsidiaries shall, directly or
indirectly, pay or cause to be paid any consideration, whether by way of
interest, fee or otherwise, to any holder of Securities or as an inducement to
any consent, waiver or amendment of any of the terms or provisions of this
Indenture or the Securities unless such consideration is offered to be paid or
agreed to be paid to all holders of the Securities that consent, waive or agree
to amend in the time frame set forth in the solicitation documents relating to
such consent, waiver or agreement.

      After an amendment, supplement or waiver under this Section becomes
effective, the Company shall mail to Securityholders a notice briefly describing
the amendment or waiver.

      SECTION 11.03     Compliance with Trust Indenture Act. Every amendment to
this Indenture or the Securities shall be set forth in a supplemental indenture
that complies with the TIA as then in effect.

      SECTION 11.04     Revocation and Effect of Consents. Until an amendment,
supplement or waiver becomes effective, a consent to it by a Securityholder of a
Security is a continuing consent by the Securityholder and every subsequent
Securityholder of a Security or portion of a Security that evidences the same
debt as the consenting Securityholder's Security, even if notation of the
consent is not made on any Security. However, any such Securityholder or
subsequent Securityholder may revoke the consent as to such Securityholder's
Security or portion of a Security if the Trustee receives the notice of
revocation before the date on which the Trustee receives an Officers'
Certificate certifying that the Securityholders of the requisite principal
amount of Securities have consented to the amendment, supplement or waiver.

      The Company may, but shall not be obligated to, fix a record date for the
purpose of determining the Securityholders entitled to consent to any amendment,
supplement or waiver. If a record date is fixed, then notwithstanding the
provisions of the immediately preceding paragraph, those persons who were
Securityholders at such record date (or their duly designated proxies), and only
those persons, shall be entitled to consent to such amendment, supplement or
waiver or to revoke any consent previously given, whether or not such persons
continue to be Securityholders after such record date. No consent shall be valid
or effective for more than 90 days after such record date unless consents from
Securityholders of the principal amount of Securities required hereunder for
such amendment or waiver to be effective shall have also been given and not
revoked within such 90-day period.

      After an amendment, supplement or waiver becomes effective it shall bind
every Securityholder, unless it is of the type described in any of clauses (a)
through (i) of Section 11.02

                                      -47-
<PAGE>
hereof. In such case, the amendment or waiver shall bind each Securityholder who
has consented to it and every subsequent Securityholder that evidences the same
debt as the consenting Securityholder's Security.

      SECTION 11.05     Notation on or Exchange of Securities. The Trustee may
place an appropriate notation about an amendment or waiver on any Security
thereafter authenticated. The Company in exchange for all Securities may issue
and the Trustee shall authenticate new Securities that reflect the amendment or
waiver.

      SECTION 11.06     Trustee Protected. The Trustee shall sign all
supplemental indentures, except that the Trustee may, but need not, sign any
supplemental indenture that adversely affects its rights. As a condition to
executing, or accepting the additional trusts created by, any supplemental
indenture permitted by this Article or the modifications thereby of the trust
created by this Indenture, the Trustee shall be entitled to receive (in addition
to those documents required by Section 12.04), and (subject to Section 315 of
the TIA) shall be fully protected in relying upon, an Opinion of Counsel stating
that the execution of such supplemental indenture is authorized or permitted by
this Indenture.

                                   ARTICLE XII

                                  Miscellaneous

      SECTION 12.01     Trust Indenture Act Controls. If any provision of this
Indenture limits, qualifies or conflicts with another provision which is deemed
to be incorporated in this Indenture by the TIA, the incorporated provision
shall control.

      SECTION 12.02     Notices. Any notice or communication by the Company or
the Trustee to the other is duly given if in writing and delivered in person or
mailed by first-class mail or overnight delivery to the other's address stated
in Section 12.10 hereof. The Company or the Trustee by notice to the other may
designate additional or different addresses for subsequent notices or
communications.

      Any notice or communication to a Securityholder shall be mailed by
first-class mail or overnight delivery to his address shown on the register kept
by the Registrar. Failure to mail a notice or communication to a Securityholder
or any defect in it shall not affect its sufficiency with respect to other
Securityholders.

      If a notice or communication is mailed in the manner provided above within
the time prescribed, it is duly given, whether or not the addressee receives it.

      If the Company mails a notice or communication to Securityholders, it
shall mail a copy to the Trustee and each Agent at the same time.

      All other notices or communications shall be in writing.

                                      -48-
<PAGE>
      In case by reason of the suspension of regular mail service, or by reason
of any other cause, it shall be impossible to mail any notice as required by the
Indenture, then such method of notification as shall be made with the approval
of the Trustee shall constitute a sufficient mailing of such notice.

      SECTION 12.03     Communication by Securityholders with Other
Securityholders.

      Securityholders may communicate pursuant to TIA Section 312(b) with other
Securityholders with respect to their rights under this Indenture or the
Securities. The Company, the Trustee, the Registrar and anyone else shall have
the protection of TIA Section 312(c).

      SECTION 12.04     Certificate and Opinion as to Conditions Precedent. Upon
any request or application by the Company to the Trustee to take any action
under this Indenture, the Company shall furnish to the Trustee:

            (a)   an Officers' Certificate stating that, in the opinion of the
signers, all conditions precedent, if any, provided for in this Indenture
relating to the proposed action have been complied with; and

            (b)   an Opinion of Counsel stating that, in the opinion of such
counsel, all such conditions precedent have been complied with.

      SECTION 12.05     Statements Required in Certificate or Opinion. Each
certificate or opinion with respect to compliance with a condition or covenant
provided for in this Indenture (other than pursuant to Section 4.03) shall
include:

            (a)   a statement that the person signing such certificate or
rendering such opinion has read such covenant or condition;

            (b)   a brief statement as to the nature and scope of the
examination or investigation upon which the statements or opinions contained in
such certificate or opinion are based;

            (c)   a statement that, in the opinion of such person, such person
has made such examination or investigation as is necessary to enable such person
to express an informed opinion as to whether or not such covenant or condition
has been complied with; and

            (d)   a statement as to whether or not, in the opinion of such
person, such condition or covenant has been complied with.

      SECTION 12.06     Rules by Trustee and Agents. The Trustee may make
reasonable rules for action by, or a meeting of, the Securityholders. The
Registrar or Paying Agent may make reasonable rules and set reasonable
requirements for its functions.

      SECTION 12.07     Legal Holidays. A "Legal Holiday" is a Saturday, a
Sunday or a day on which banking institutions in the State of New York or the
State of California are not required to be open. If a payment date is a Legal
Holiday at a place of payment, payment may be made at that

                                      -49-
<PAGE>
place on the next succeeding day that is not a Legal Holiday, and no interest
shall accrue for the intervening period. If any other operative date for
purposes of this Indenture shall occur on a Legal Holiday then for all purposes
the next succeeding day that is not a Legal Holiday shall be such operative
date.

      SECTION 12.08     No Recourse Against Others. A director, officer,
employee or shareholder, as such, of the Company shall not have any liability
for any obligations of the Company under the Securities or the Indenture or for
any claim based on, in respect of or by reason of such obligations or their
creation. Each Securityholder by accepting a Security waives and releases all
such liability. The waiver and release are part of the consideration for the
issue of the Securities.

      SECTION 12.09     Counterparts. This Indenture may be executed in any
number of counterparts and by the parties hereto in separate counterparts, each
of which when so executed shall be deemed to be an original and all of which
taken together shall constitute one and the same agreement.

      SECTION 12.10     Variable Provisions. "Officer" means the Chairman of the
Board, the President, any Vice-President (whether or not designated by a number
or a word or words added before or after the title "Vice President"), the Chief
Financial Officer, the Treasurer, the Secretary, any Assistant Treasurer or any
Assistant Secretary of the Company.

      The first certificate pursuant to Section 4.03 hereof shall be for the
fiscal year ending on December 31, 2002.

      The reporting date for Section 9.06 hereof is March 15 of each year. The
first reporting date is March 15, 2003.

      The Trustee (or if the Trustee is a member of a bank holding company
system, its bank holding company) shall always have a combined capital and
surplus of at least $50,000,000 as set forth in its most recent published annual
report of condition.

      The Company's address for purposes of the Indenture is:

            Chief Financial Officer
            Intevac, Inc.
            3550 Bassett Street
            Santa Clara, California 95054
            Telephone Number: (408) 986-9888
            Telefax Number: (408) 988-8145

      The Trustee's address is:

            State Street Bank and Trust Company of California, N. A.
            633 West 5th Street, 12th Floor
            Los Angeles, CA 90071

                                      -50-
<PAGE>
            Attention: Corporate Trust Administration
            (Intevac, Inc. 6-1/2% Convertible Subordinated Notes due 2009)
            Telephone Number: (213) 362-7334
            Telefax Number: (213) 362-7357

      The Company or the Trustee may change its address for purposes of this
Indenture by written notice to the other.

      SECTION 12.11     GOVERNING LAW. THIS INDENTURE AND THE SECURITIES ISSUED
HEREUNDER SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE
STATE OF NEW YORK.

      SECTION 12.12     No Adverse Interpretation of Other Agreements. This
Indenture may not be used to interpret another indenture, loan or debt agreement
of the Company or an Affiliate. Any such indenture, loan or debt agreement may
not be used to interpret this Indenture.

      SECTION 12.13     Successors. All agreements of the Company in this
Indenture and the Securities shall bind its successor. All agreements of the
Trustee in this Indenture shall bind its successor.

      SECTION 12.14     Severability. In case any provision in this Indenture or
in the Securities shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.

      SECTION 12.15     Table of Contents, Headings, Etc. The Table of Contents
and headings of the Articles and Sections of this Indenture have been inserted
for convenience of reference only, are not to be considered a part hereof, and
shall in no way modify or restrict any of the terms or provisions hereof.

                                  ARTICLE XIII

                                Repurchase Offer

      SECTION 13.01     Repurchase Offer.

            (a)   In the event that, pursuant to Section 4.09 hereof, the
Company shall commence a Repurchase Offer, the Company shall follow the
procedures in this Section 13.01.

            (b)   The Repurchase Offer shall remain open for a period specified
by the Company which shall be no less than 30 calendar days and no more than 40
calendar days prior to the Repurchase Payment Date, except to the extent that a
longer period is required by applicable law. The first day of such period is
referred to as the "Repurchase Commencement Date". On the Repurchase Payment
Date the Company shall purchase the principal amount of any Securities required
to be purchased pursuant to Section 4.09 hereof (the "Repurchase Offer Amount").

                                      -51-
<PAGE>
            (c)   If the Repurchase Payment Date is on or after an interest
payment record date and on or before the related interest payment date, any
accrued interest, to the related interest payment date will be paid to the
person in whose name a Security is registered at the close of business on such
record date, and no additional interest, will be payable to Securityholders who
tender Securities pursuant to the Repurchase Offer.

      SECTION 13.02     Repurchase Notice.

            (a)   The Company shall provide the Trustee with written notice of
the Repurchase Offer at least 10 Business Days prior to the mailing of the
notice of the Repurchase Offer to the Securityholders.

            (b)   On or before the date that is 90 days prior to the Repurchase
Payment Date, the Company or the Trustee (at the request and expense of the
Company) shall send, by first class mail, a notice to each of the
Securityholders, which shall govern the terms of the Repurchase Offer and shall
state:

                  (i)   that the Repurchase Offer is being made pursuant to
Section 13.01 and Section 4.09 hereof and that all Securities tendered will be
accepted for payment;

                  (ii)  the Repurchase Payment (as determined in accordance with
Section 4.09 hereof), the length of time the Repurchase Offer will remain open
and the Repurchase Payment Date;

                  (iii) that any Security or portion thereof not tendered or
accepted for payment will continue to accrue interest;

                  (iv)  that, unless the Company defaults in the payment of the
Repurchase Payment, any Security or portion thereof accepted for payment
pursuant to the Repurchase Offer shall cease to accrue interest after the
Repurchase Payment Date;

                  (v)   that Securityholders electing to have a Security or
portion thereof purchased pursuant to any Repurchase Offer will be required to
surrender the Security, with the form entitled "Option of Securityholder To
Elect Purchase" on the reverse of the Security completed, to the Paying Agent at
the address specified in the notice prior to the close of business on the third
Business Day preceding the Repurchase Payment Date;

                  (vi)  that Securityholders will be entitled to withdraw their
election if the Paying Agent receives, not later than the close of business on
the second Business Day preceding the Repurchase Payment Date, or such longer
period as may be required by law, a letter or a telegram, telex, facsimile
transmission (receipt of which is confirmed and promptly followed by a letter)
setting forth the name of the Securityholder, the principal amount of the
Security or portion thereof the Securityholder delivered for purchase and a
statement that such Securityholder is withdrawing his election to have the
Security or portion thereof purchased; and

                                      -52-
<PAGE>
                  (vii) that Securityholders whose Securities are being
purchased only in part will be issued new Securities equal in principal amount
to the unpurchased portion of the Securities surrendered, which unpurchased
portion must be equal to $1,000 in principal amount or an integral multiple
thereof.

      In addition, the notice shall contain all instructions and materials that
the Company shall reasonably deem necessary to enable such Securityholders to
tender Securities pursuant to the Repurchase Offer.

      SECTION 13.03     Deposit of Repurchase Offer Amount.

      On or prior to the Repurchase Payment Date, the Company shall irrevocably
deposit with the Trustee or a Paying Agent in immediately available funds an
amount equal to the Repurchase Payment to be held for payment in accordance with
the terms of this Section13.03. On the Repurchase Payment Date, the Company
shall, to the extent lawful, (i) accept for payment the Securities or portions
thereof tendered pursuant to the Repurchase Offer, (ii) deliver or cause to be
delivered to the Trustee Securities so accepted and (iii) deliver to the Trustee
an Officers' Certificate stating that such Securities or portions thereof have
been accepted for payment by the Company in accordance with the terms of this
Section13.03. The Paying Agent shall promptly (but in any case not later than
five calendar days after the Repurchase Payment Date) mail or deliver to each
tendering Securityholder an amount equal to the Repurchase Payment of the
Securities tendered by such Securityholder, and the Trustee shall promptly
authenticate and mail or deliver to such Securityholders a new Security equal in
principal amount to any unpurchased portion of the Security surrendered, if any;
provided, that each new Security shall be in a principal amount of $1,000 or an
integral multiple thereof. Any Securities not so accepted shall be promptly
mailed or delivered by or on behalf of the Company to the holder thereof. The
Company will publicly announce the results of the Repurchase Offer on, or as
soon as practicable after, the Repurchase Payment Date.

      SECTION 13.04     Compliance with Applicable Laws.

      The Repurchase Offer shall be made by the Company in compliance with all
applicable provisions of the Exchange Act, and all applicable tender offer rules
promulgated thereunder, and shall include all instructions and materials that
the Company shall reasonably deem necessary to enable such Securityholders to
tender their Securities.

                  [Remainder of page intentionally left blank]

                                      -53-
<PAGE>
      IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed, all as of the date first written above.

                                              INTEVAC, INC.,
                                              AS COMPANY,

                                              By:  /s/ Charles B. Eddy III
                                              ----------------------------------
                                              Name: Charles Eddy
                                              Title: CFO

                                              STATE STREET BANK AND TRUST
                                              COMPANY OF CALIFORNIA, N.A.,
                                              AS TRUSTEE,

                                              By:  /s/ Joni D'Amico
                                              ----------------------------------
                                              Name:  Joni D'Amico
                                              Title:  Vice President
<PAGE>
                                    EXHIBIT A

                      FORM OF CONVERTIBLE SUBORDINATED NOTE

                             [FORM OF FACE OF NOTE]

                           [GLOBAL SECURITIES LEGEND]

      UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), TO THE COMPANY OR
ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS
REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO
CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC) ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

      TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE,
BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH
SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE
LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE
INDENTURE REFERRED TO ON THE REVERSE HEREOF.

                                      A-1

<PAGE>

No. _______                                                            Cusip No.

                                  INTEVAC, INC.

                 6-1/2% CONVERTIBLE SUBORDINATED NOTE DUE 2009

      Intevac, Inc., a California corporation (the "Company") for value received
promises to pay to _____________________________________________________ or its
registered assigns, the principal sum [indicated on Schedule A hereof]* [of
________ Dollars]** on March 1, 2009 at the office or agency of the Company
maintained for that purpose in the Borough of Manhattan, The City of New York,
State of New York, and to pay interest on said principal sum at the rate of
6-1/2% per annum, as more specifically described on the reverse hereof.

Interest Payment Dates:   March 1 and September 1, commencing September 1, 2002.
Record Dates:             February 15 and August 15.

      Reference is hereby made to the further provisions of this Note set forth
on the reverse hereof, which further provisions shall for all purposes have the
same effect as if set forth at this place.

_____________
  * Applicable to Global Securities only.

 ** Applicable to certificated Securities only.

                                       A-2

<PAGE>

      IN WITNESS WHEREOF, Intevac, Inc. has caused this Note to be signed
manually or by facsimile by its duly authorized Officers.

Dated: ____________________________

                                            INTEVAC, INC.

                                            By: ____________________________

                                            By: ____________________________

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is one of the 6-1/2% Convertible Subordinated Notes
due 2009 described in the within-mentioned Indenture.

State Street Bank and Trust Company of California, N.A.,
as Trustee

By: ________________________

    Authorized Officer

                                      A-3
<PAGE>

                                  INTEVAC, INC.

                  6-1/2% CONVERTIBLE SUBORDINATED NOTE DUE 2009

      1. Interest. INTEVAC, INC., a California corporation (the "Company"), is
the issuer of the 6-1/2% Convertible Subordinated Notes due 2009 (the "Notes"),
of which this Note is a part. The Company promises to pay interest on the Notes
in cash semiannually on each March 1 and September 1, commencing on September 1,
2002, to holders of record on the immediately preceding February 15 and August
15.

      Interest on the Notes will accrue from the most recent date to which
interest has been paid or duly provided for, or if no interest has been paid or
duly provided for, from July 12, 2002 until payment of said principal sum has
been made or duly provided for. Interest will be computed on the basis of a
360-day year of twelve 30-day months. To the extent lawful, the Company shall
pay interest (including post-petition interest in any proceeding under any
Bankruptcy Law) on overdue installments of interest (without regard to any
applicable grace period) at the rate borne by the Notes, compounded annually.

      2. Method of Payment. The Company will pay interest on the Notes (except
defaulted interest) to the persons who are registered holders of the Notes at
the close of business on the record date for the next interest payment date even
though Notes are canceled after the record date and on or before the interest
payment date. The Securityholder hereof must surrender Notes to a Paying Agent
to collect principal payments. The Company will pay principal and interest in
money of the United States that at the time of payment is legal tender for
payment of public and private debts. However, the Company may pay principal and
interest by check payable in such money. It may mail a check for interest to a
holders' registered address; provided that a holder of Notes with an aggregate
principal amount in excess of $2,000,000 will be paid by wire transfer in
immediately available funds at the election of the holder.

      3. Paying Agent and Registrar. The Trustee will act initially as Paying
Agent, Registrar and Conversion Agent. The Company may change any Paying Agent,
Registrar, co-registrar or Conversion Agent without prior notice. The Company or
any of its Affiliates may act in any such capacity.

      4. Indenture. The Company issued the Notes under an indenture, dated as of
July 12, 2002 (the "Indenture"), between the Company and State Street Bank and
Trust Company of California, N.A., as Trustee. The terms of the Notes include
those stated in the Indenture and those incorporated into the Indenture from the
Trust Indenture Act of 1939, and rules and regulations thereunder. The Notes are
subject to, and qualified by, all such terms, certain of which are summarized
hereon, and Securityholders are referred to the Indenture and such Act for a
statement of such terms. The Notes are general unsecured obligations of the
Company limited to an aggregate principal amount at maturity of $29,543,000. The
Indenture does not limit the ability of the Company or any of its Subsidiaries
to incur indebtedness or to grant security interests or liens in respect of
their assets.

                                      A-4
<PAGE>

      5. Optional Redemption. The Notes are subject to redemption at the option
of the Company, in whole or from time to time in part (in any integral multiple
of $1,000), on any date on or after March 1, 2005 at 100% of the principal
amount, but excluding the redemption date (subject to the right of holders of
record on the relevant record date to receive interest due on an interest
payment date). On or after the redemption date, interest will cease to accrue on
the Notes, or portion thereof, called for redemption.

      6. Notice of Redemption. Notice of redemption will be mailed at least 15
days but not more than 60 days before the redemption date to each holder of the
Notes to be redeemed at his address of record. The Notes in denominations larger
than $1,000 may be redeemed in part but only in integral multiples of $1,000. In
the event of a redemption of less than all of the Notes, the Notes will be
chosen for redemption by the Trustee in accordance with the Indenture. Unless
the Company defaults in making such redemption payment, or the Paying Agent is
prohibited from making such payment pursuant to the Indenture, by law or
otherwise, interest shall cease to accrue on the Notes or portions of them
called for redemption on and after the redemption date. If this Note is redeemed
subsequent to a record date with respect to any interest payment date specified
above and on or prior to such interest payment date, then any accrued interest
will be paid to the person in whose name this Note is registered at the close of
business on such record date.

      7. Mandatory Redemption. The Company will not be required to make
mandatory redemption payments with respect to the Notes. There are no sinking
fund payments with respect to the Notes.

      8. Repurchase at Option of Holder. If there is a Designated Event, the
Company shall be required to offer to purchase on the Designated Event Payment
Date all outstanding Notes at a purchase price equal to 101% of the principal
amount thereof on the date of purchase, plus accrued and unpaid interest to the
Designated Event Payment Date. Holders of Notes that are subject to an offer to
purchase will be mailed a Designated Event Offer from the Company prior to any
related Designated Event Payment Date and may elect to have such Notes or
portions thereof in authorized denominations purchased by completing the form
entitled "Option of Securityholder To Elect Purchase" appearing below.
Securityholders have the right to withdraw their election by delivering a
written notice of withdrawal to the Company or the Paying Agent in accordance
with the terms of the Indenture.

      If there is a Triggering Distribution (as defined in the Indenture), the
Company shall be required to offer to purchase on the Repurchase Payment Date
all outstanding Notes at a purchase price equal to 100% of the principal amount
thereof together with any accrued and unpaid interest to the Repurchase Payment
Date. Holders of Notes that are subject to an offer to purchase will be mailed a
Repurchase Offer from the Company on or before the date that is 90 days prior to
any related Repurchase Payment Date and may elect to have such Notes or portions
thereof in authorized denominations purchased by completing the form entitled
"Option of Securityholder To Elect Purchase" appearing below. Securityholders
have the right to withdraw their election by delivering a written notice of
withdrawal to the Company or the Paying Agent in accordance with the terms of
the Indenture.
                                      A-5

<PAGE>

      9. Subordination. The payment of the principal of, interest on or any
other amounts due on the Notes is subordinated in right of payment to all
existing and future Senior Debt of the Company, as described in the Indenture.
Each Securityholder, by accepting a Note, agrees to such subordination and
authorizes and directs the Trustee on its behalf to take such action as may be
necessary or appropriate to effectuate the subordination so provided and
appoints the Trustee as its attorney-in-fact for such purpose.

      10. Conversion. The holder of any Note has the right, exercisable at any
time prior to the close of business on the Note's maturity, to convert the
principal amount thereof (or any portion thereof that is an integral multiple of
$1,000) into shares of Common Stock at the initial Conversion Price of $7.00 per
share, subject to adjustment under certain circumstances, except that if a Note
is called for redemption, the conversion right will terminate at the close of
business (New York time) on the Business Day immediately preceding the date
fixed for redemption.

      To convert a Note, a holder must (1) complete and sign a notice of
election to convert substantially in the form set forth below, (2) surrender the
Note to a Conversion Agent, (3) furnish appropriate endorsements or transfer
documents if required by the Registrar or Conversion Agent and (4) pay any
transfer or similar tax, if required. Upon conversion, no adjustment or payment
will be made for interest or dividends, but if any Securityholder surrenders a
Note for conversion after the close of business on the record date for the
payment of an installment of interest and prior to the opening of business on
the next interest payment date, then, notwithstanding such conversion, the
interest payable on such interest payment date will be paid to the registered
holder of such Note on such record date. In such event, such Note, when
surrendered for conversion, must be accompanied by payment in funds acceptable
to the Company of an amount equal to the interest payable on such interest
payment date on the portion so converted, unless such Security has been called
for redemption on or prior to such interest payment date. The number of shares
of Common Stock issuable upon conversion of a Note is determined by dividing the
principal amount of the Note converted by the Conversion Price in effect on the
Conversion Date. No fractional shares will be issued upon conversion but a cash
adjustment will be made for any fractional interest.

      A Note in respect of which a holder has delivered an "Option of
Securityholder to Elect Purchase" form appearing below exercising the option of
such holder to require the Company to purchase such Note may be converted only
if the notice of exercise is withdrawn as provided above and in accordance with
the terms of the Indenture. The above description of conversion of the Notes is
qualified by reference to, and is subject in its entirety by, the more complete
description thereof contained in the Indenture.

      11. Automatic Conversion. The Company may elect to automatically convert
the Notes on or prior to maturity if the Daily Market Price of the Common Stock
has exceeded 150% of the Conversion Price for at least 20 Trading Days out of
the 30 consecutive Trading Days ending within five Trading Days prior to the
Automatic Conversion Notice.

      12. Denominations Transfer, Exchange. The Notes are in registered form,
without coupons, in denominations of $1,000 and integral multiples of $1,000.
The transfer of Notes may be registered, and Notes may be exchanged, as provided
in the Indenture. The Registrar may require a

                                      A-6
<PAGE>

Securityholder, among other things, to furnish appropriate endorsements and
transfer documents and to pay any taxes and fees required by law or permitted by
the Indenture. The Company is not required to exchange or register the transfer
of (i) any Note for a period of 15 days next preceding any selection of Notes to
be redeemed, (ii) any Note or portion thereof selected for redemption or (iii)
any Note or portion thereof surrendered for repurchase (and not withdrawn) in
connection with a Designated Event.

      13. Persons Deemed Owners. Except as provided in paragraph 2 of this Note,
the registered Securityholder of a Note may be treated as its owner for all
purposes.

      14. Unclaimed Money. If money for the payment of principal or interest
remains unclaimed for two years, the Trustee and the Paying Agent shall pay the
money back to the Company at its request. After that, Securityholders of Notes
entitled to the money must look to the Company for payment, unless an abandoned
property law designates another person, and all liability of the Trustee and
such Paying Agent with respect to such money shall cease.

      15. Defaults and Remedies. The Notes shall have the Events of Default as
set forth in Section 8.01 of the Indenture. Subject to certain limitations in
the Indenture, if an Event of Default occurs and is continuing, the Trustee by
notice to the Company or the Securityholders of at least 25% in aggregate
principal amount of the then-outstanding Notes by notice to the Company and the
Trustee may declare all the Notes to be due and payable immediately, except that
in the case of an Event of Default arising from certain events of bankruptcy or
insolvency, Notes shall become due and payable immediately without further
action or notice. Upon acceleration as described in either of the preceding
sentences, the subordination provisions of the Indenture preclude any payment
being made to Securityholders for at least 5 Business Days after holders of
Senior Debt receive notice of such acceleration except as otherwise provided in
the Indenture.

      The Securityholders of a majority in principal amount of the Notes then
outstanding by written notice to the Trustee may rescind an acceleration and its
consequences if the rescission would not conflict with any judgment or decree
and if all existing Events of Default have been cured or waived except
nonpayment of principal or interest that has become due solely because of the
acceleration. Securityholders may not enforce the Indenture or the Notes except
as provided in the Indenture. Subject to certain limitations, Securityholders of
a majority in principal amount of the then-outstanding Notes issued under the
Indenture may direct the Trustee in its exercise of any trust or power. The
Company must furnish compliance certificates to the Trustee annually. The above
description of Events of Default and remedies is qualified by reference to, and
subject in its entirety by, the more complete description thereof contained in
the Indenture.

      16. Amendments, Supplements and Waivers. Subject to certain exceptions,
the Indenture or the Notes may be amended or supplemented with the consent of
the Securityholders of at least a majority in principal amount of the
then-outstanding Notes (including consents obtained in connection with a tender
offer or exchange offer for Notes), and any existing default may be waived with
the consent of the Securityholders of a majority in principal amount of the
then-outstanding Notes, including consents obtained in connection with a tender
offer or exchange offer for Notes. Without the consent of any Securityholder,
the Indenture or the Notes may be amended, among other

                                      A-7
<PAGE>

things, to cure any ambiguity, defect or inconsistency, to provide for
assumption of the Company's obligations to Securityholders in the case of a
merger, consolidation or sale or transfer of all or substantially all of the
Company's properties or assets pursuant to Article VII of the Indenture, to make
any change that would provide any additional rights or benefits to
Securityholders or that does not adversely affect the legal rights under the
Indenture of any Securityholder, to qualify the Indenture under the TIA, or to
comply with the requirements of the SEC in order to maintain the qualification
of the Indenture under the TIA.

      17. Trustee Dealings with the Company. The Trustee, in its individual or
any other capacity, may become the owner or pledgee of the Notes and may
otherwise deal with the Company or an Affiliate with the same rights it would
have, as if it were not Trustee, subject to certain limitations provided for in
the Indenture and in the TIA. Any Agent may do the same with like rights.

      18. No Recourse Against Others. A director, officer, employee or
shareholder, as such, of the Company shall not have any liability for any
obligations of the Company under the Notes or the Indenture or for any claim
based on, in respect of or by reason of such obligations or their creation. Each
Securityholder, by accepting a Note, waives and releases all such liability. The
waiver and release are part of the consideration for the issue of the Notes.

      19. Governing Law. THE INDENTURE AND THE SECURITIES ISSUED HEREUNDER SHALL
BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW
YORK.

      20. Authentication. The Notes shall not be valid until authenticated by
the manual signature of an authorized officer of the Trustee or an
authenticating agent.

      21. Abbreviations. Customary abbreviations may be used in the name of a
Securityholder or an assignee, such as: TEN COM (for tenants in common), TENANT
(for tenants by the entireties), JT TEN (for joint tenants with right of
survivorship and not as tenants in common), CUST (for Custodian), and U/G/M/A
(for Uniform Gifts to Minors Act).

      22. Definitions. Capitalized terms not defined in this Note have the
meaning given to them in the Indenture.

The Company will furnish to any
Securityholder of the Notes upon written request and without charge a copy of
the Indenture and the Registration Agreement. Request may be made to:

        Investor Relations
        Intevac, Inc.
        3560 Bassett Street
        Santa Clara, California 95054
        Telephone Number: (408) 986-9888

                                       A-8

<PAGE>
                  ASSIGNMENT AND CERTIFICATE OF TRANSFER FORM

                  To assign this Note, fill in the form below:

                  (I) or (we) assign and transfer this Note to

________________________________________________________________________________
               (Insert assignee's social security or tax I.D. no.)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
            (Print or type assignee's name, address and zip code)

and irrevocably appoint ________________  agent to transfer this Note on the
books of the Company.  The agent may substitute another to act for him.

      Your Signature: __________________________________________________________
                               (Sign exactly as your name appears
                                 on the other side of this Note)
      Date: _________________________

      Signature Guarantee***: __________________________________________________

_____________
*** Signature must be guaranteed by a commercial bank, trust company or member
    firm of the New York Stock Exchange.

                                      A-9
<PAGE>

                      [TO BE ATTACHED TO GLOBAL SECURITIES]

                                   SCHEDULE A
   The initial principal amount at maturity of this Global Security shall be
  $29,543,000. The following increases or decreases in the principal amount of
                      this Global Security have been made:

<TABLE>
<CAPTION>

             AMOUNT OF
             INCREASE IN
              PRINCIPAL                         PRINCIPAL
            AMOUNT OF THIS                   AMOUNT OF THIS
           GLOBAL SECURITY     AMOUNT OF         GLOBAL
            INCLUDING UPON    DECREASE IN       SECURITY         SIGNATURE OF
             EXERCISE OF       PRINCIPAL     FOLLOWING SUCH   AUTHORIZED OFFICER
            OVERALLOTMENT    AMOUNT OF THIS    DECREASE OR       OF TRUSTEE OR
DATE MADE       OPTION      GLOBAL SECURITY     INCREASE           CUSTODIAN
<S>        <C>              <C>               <C>             <C>
---------       ------      ---------------     --------           ---------
---------       ------      ---------------     --------           ---------
---------       ------      ---------------     --------           ---------
---------       ------      ---------------     --------           ---------
</TABLE>

                                      A-10
<PAGE>

                   OPTION OF SECURITYHOLDER TO ELECT PURCHASE

       If you want to elect to have this Note or a portion thereof repurchased
by the Company pursuant to Section 3.08 or 4.08 of the Indenture, check the
box: / /

      If you want to elect to have this Note or a portion thereof repurchased by
the Company pursuant to Article XIII and Section 4.09 of the Indenture, check
the box: / /

      If the puirchase is in part, indicate the portion ($1,000 or any integral
multiple thereof) to be purchased:

      Your Signature: __________________________________________________________
                               (Sign exactly as your name appears
                                 on the other side of this Note)

      Date: _________________________

      Signature Guarantee*: ________________________________

_________
* Signature must be guaranteed by a commercial bank, trust company or member
  firm of the New York Stock Exchange.

                                      A-11
<PAGE>

                               ELECTION TO CONVERT

To: Intevac, Inc.

      The undersigned owner of this Note hereby irrevocably exercises the option
to convert this Note, or the portion below designated, into Common Stock of
Intevac, Inc. in accordance with the terms of the Indenture referred to in this
Note, and directs that the shares issuable and deliverable upon conversion,
together with any check in payment for fractional shares, be issued in the name
of and delivered to the undersigned, unless a different name has been indicated
in the assignment below. If shares are to be issued in the name of a person
other than the undersigned, the undersigned will pay all transfer taxes payable
with respect thereto.

Date: ____________________________

      In whole ________      Or            Portion of Note to be converted
                                           ($1,000 or any integral multiple
                                           thereof):
                                                  $________________

      Your Signature:___________________________________________________________
                               (Sign exactly as your name appears
                                 on the other side of this Note)

      Please print or typewrite name and address, including zip code, and Social
      Security or other identifying number

      Signature Guarantee*: ____________________________________________________

________________
  * Signature must be guaranteed by a commercial bank, trust company or member
    firm of the New York Stock Exchange.

                                      A-12

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