<PAGE>

                                                                    Exhibit 10.2

                                                                  EXECUTION COPY



                      5.75% CONVERTIBLE SUBORDINATED NOTES

               WITH AUTO-CONVERSION PROVISION DUE 2006 (SNAPs(SM))



                          REGISTRATION RIGHTS AGREEMENT



                          Dated as of November 14, 2001

                                     between

                                  SEPRACOR INC.
                                 as the Company,

                                       and

                            ROBERTSON STEPHENS, INC.
                                as the Purchaser

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                                                                  EXECUTION COPY



                          REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement is made and entered into as of
November 14, 2001 between Sepracor, Inc., a Delaware corporation (the
"COMPANY"), and Robertson Stephens, Inc. (the "PURCHASER"), who has purchased
or has the right to purchase up to $400,000,000 in aggregate principal amount
of 5.75% Convertible Subordinated Notes with Auto-Conversion Provision due
2006 (SNAPs(SM)) (or up to $500,000,000 if the option set forth in Section
2(b) of the Purchase Agreement (as defined below) is exercised in full by the
Purchaser) of the Company pursuant to the Purchase Agreement.

     This Agreement is made pursuant to the Purchase Agreement, dated November
8, 2001 between the Company and the Purchaser (the "PURCHASE AGREEMENT"). In
order to induce the Purchaser to enter into the Purchase Agreement, the Company
has agreed to provide the registration rights provided for in this Agreement to
the Purchaser and its respective direct and indirect transferees (i) for the
benefit of the Purchaser, (ii) for the benefit of the holders from time to time
of the Notes (as such term is defined in Section 1 hereof) (including the
Purchaser) and the holders from time to time of the Common Stock (as such term
is defined in Section 1 hereof) issuable or issued upon conversion of the Notes
and (iii) for the benefit of the securities constituting the Transfer Restricted
Securities (as such term is defined in Section 1 hereof). The execution of this
Agreement is a condition to the closing of the transactions contemplated by the
Purchase Agreement.

     The parties hereby agree as follows:

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

          ACT: As defined in the last paragraph of this Section 1.

          ADVICE: As defined in Section 2(d) hereof.

          AFFILIATE: An affiliate of any specified person shall mean 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," when used with respect to any person, means the power to
direct the management and policies of such person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise and
the terms "affiliated," "controlling" and "controlled" have meanings correlative
to the foregoing.

          AGREEMENT: This Registration Rights Agreement, as the same may be
amended, supplemented or modified from time to time in accordance with the terms
hereof.

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          BUSINESS DAY: Each Monday, Tuesday, Wednesday, Thursday and Friday
that is not a day on which banking institutions in New York, New York are
authorized or obligated by law or executive order to close.

          CLOSING DATE: November 14, 2001.

          COMMON STOCK: Common Stock, $.10 par value per share, of the Company
and any other shares of common stock as may constitute "Common Stock" for
purposes of the Indenture, in each case, as issuable or issued upon conversion
of the Notes.

          COMPANY: Sepracor, Inc., a Delaware corporation, and any successor
corporation thereto.

          COMPANY INDEMNIFIED PERSON: As defined in Section 6(c) hereof.

          CONTROLLING PERSON: As defined in Section 6(a) hereof.

          DAMAGES PAYMENT DATE: Each of the semi-annual interest payment dates
provided in the Indenture.

          EFFECTIVENESS PERIOD: As defined in Section 2(a) hereof.

          EFFECTIVENESS TARGET DATE: The 180thday following the Closing Date.

          EXCHANGE ACT: The Securities Exchange Act of 1934, as amended, and the
rules and regulations promulgated by the SEC thereunder.

          FILING DATE: The 60th day after the Closing Date.

          HOLDER: Each owner of any Transfer Restricted Securities.

          INDEMNIFIED PERSON: As defined in Section 6(a) hereof.

          INDEMNIFIED PARTY: As defined in Section 6(c) hereof.

          INDEMNIFYING PARTY: The Company, on one hand, or any Holder (or
predecessor Holder), on the other hand, as applicable, in accordance with
Section 6 hereof.

          INDENTURE: The Indenture, dated as of the date hereof, between the
Company and the Trustee, pursuant to which the Notes are being issued, as the
same may be amended, modified or supplemented from time to time in accordance
with the terms thereof.

          LIQUIDATED DAMAGES: As defined in Section 3(a) hereof.

          NOTES: The $400,000,000 aggregate principal amount of 5.75%
Convertible Subordinated Notes with Auto-Conversion Provision due 2006
(SNAPs(SM)) of the Company being

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issued pursuant to the Indenture (or $500,000,000 if the option set forth in
Section 2(b) of the Purchase Agreement is exercised in full by the Purchaser).

          NOTICE AND QUESTIONNAIRE: A written notice delivered to the Company
containing substantially the information called for by the Selling
Securityholder Notice and Questionnaire attached as ANNEX A to the Offering
Circular of the Company dated November 8, 2001 relating to the Notes.

          PROCEEDING: An action, claim, suit or proceeding (including, without
limitation, an investigation or partial proceeding, such as a deposition),
whether commenced or threatened.

          PROSPECTUS: The prospectus included in any Registration Statement, as
amended or supplemented by any prospectus supplement, with respect to the resale
of any of the Transfer Restricted Securities covered by such Registration
Statement, and all other amendments and supplements to any such prospectus,
including post-effective amendments, and all materials incorporated by reference
or deemed to be incorporated by reference, if any, in such prospectus.

          PURCHASE AGREEMENT: As defined in the second paragraph hereof.

          PURCHASER: As defined in the first paragraph hereof.

          RECORD HOLDER: (i) with respect to any Damages Payment Date relating
to any Note as to which any such Liquidated Damages have accrued, the registered
Holder of such Note on the record date with respect to the interest payment date
under the Indenture on which such Damages Payment Date shall occur and (ii) with
respect to any Damages Payment Date relating to any shares of Common Stock as to
which any such Liquidated Damages have accrued, the registered Holder of such
shares 15 days prior to the next succeeding Damages Payment Date.

          REGISTRATION DEFAULT: As defined in Section 3(a) hereof.

          REGISTRATION STATEMENT: Any registration statement of the Company
filed with the SEC pursuant to the Securities Act that covers the resale of any
of the Transfer Restricted Securities pursuant to the provisions of this
Agreement, including the Prospectus, amendments and supplements to such
registration statement or Prospectus, including pre- and post-effective
amendments, all exhibits thereto, and all material incorporated by reference or
deemed to be incorporated by reference, if any, in such registration statement.

          REQUISITE INFORMATION: As defined in Section 2(c) hereof.

          RESTRICTED NOTES: Notes required pursuant to the Indenture to bear the
legend set forth in Section 2.5(d) of the Indenture.

          RULE 144: Rule 144 promulgated by the SEC pursuant to the Securities
Act, as such rule may be amended from time to time, or any successor rule or
regulation.

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          RULE 144A: Rule 144A promulgated by the SEC pursuant to the Securities
Act, as such rule may be amended from time to time, or any successor rule or
regulation.

          RULE 415: Rule 415 promulgated by the SEC pursuant to the Securities
Act, as such rule may be amended from time to time, or any successor rule or
regulation.

          RULE 424: Rule 424 promulgated by the SEC pursuant to the Securities
Act, as such rule may be amended from time to time, or any successor rule or
regulation.

          SEC: The Securities and Exchange Commission.

          SECURITIES ACT: The Securities Act of 1933, as amended, and the rules
and regulations promulgated by the SEC thereunder.

          SHELF REGISTRATION STATEMENT: As defined in Section 2(a) hereof.

          SPECIAL COUNSEL: The special counsel to the Holders.

          TIA: The Trust Indenture Act of 1939, as amended, and the rules and
regulations promulgated by the SEC thereunder.

          TRANSFER RESTRICTED SECURITIES: The Restricted Notes and the shares of
Common Stock into which such Restricted Notes are converted or convertible
(including any shares of Common Stock issued or issuable thereon upon any stock
split, stock combination, stock dividend or the like) upon original issuance
thereof, and at all times subsequent thereto, and associated related rights, if
any, until, in the case of any such Restricted Note or shares of Common Stock
(and associated rights) (i) the date on which the resale thereof has been
effectively registered under the Securities Act and disposed of in accordance
with the Registration Statement relating thereto, (ii) the date on which such
security has been distributed to the public pursuant to Rule 144 or is saleable
pursuant to paragraph (k) of Rule 144 or (iii) the date on which such security
ceases to be outstanding, whichever date is earliest.

          TRUSTEE: The trustee under the Indenture.

          UNDERWRITTEN REGISTRATION OR UNDERWRITTEN OFFERING: A registration in
connection with which securities of the Company are sold to one or more
underwriters for reoffering to the public pursuant to an effective Registration
Statement.

          References herein to the term "Holders of a majority in aggregate
principal amount of Transfer Restricted Securities" or words to a similar effect
shall mean, with respect to any request, notice, demand, objection or other
action by the Holders hereunder or pursuant hereto (each, an "Act"), registered
Holders of a number of shares of then-outstanding Common Stock constituting
Transfer Restricted Securities and an aggregate principal amount of then
outstanding Notes constituting Transfer Restricted Securities, such that the sum
of such shares of Common Stock and the shares of Common Stock issuable upon
conversion of such Notes constitutes in excess of 50% of the sum of all of the
then-outstanding shares of Common Stock constituting Transfer Restricted


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Securities and the number of shares of Common Stock issuable upon conversion of
then-outstanding Notes constituting Transfer Restricted Securities. For purposes
of the preceding sentence, Transfer Restricted Securities owned, directly or
indirectly, by the Company or its Affiliates shall be deemed not to be
outstanding.

     2. SHELF REGISTRATION STATEMENT

          (a) The Company agrees to file with the SEC as soon as reasonably
practicable after the Closing Date, but in no event later than the Filing Date,
a Registration Statement for an offering to be made on a continuous basis
pursuant to Rule 415, covering all of the Transfer Restricted Securities or
separate Registration Statements for an offering to be made on a continuous
basis pursuant to Rule 415 covering all of the Notes constituting Transfer
Restricted Securities and all of the Common Stock constituting Transfer
Restricted Securities, respectively (such Registration Statement or Statements,
collectively, the "SHELF REGISTRATION STATEMENT"). The Shelf Registration
Statement shall be on Form S-3 under the Securities Act or another appropriate
form selected by the Company permitting registration of such Transfer Restricted
Securities for resale by the Holders in the manner or manners reasonably
designated by Holders of a majority in aggregate principal amount of Transfer
Restricted Securities being sold; provided, however, that the Company shall be
required to participate in only one underwritten offering, in the aggregate, in
connection with the Shelf Registration Statement and all Subsequent Registration
Statements. The Company shall not permit any securities other than the Transfer
Restricted Securities to be included in the initial Shelf Registration
Statement. The Company shall use its reasonable best efforts to cause the Shelf
Registration Statement to be declared effective pursuant to the Securities Act
as soon as reasonably practicable following the filing thereof and to keep the
Shelf Registration Statement continuously effective under the Securities Act for
two years after the latest date of original issuance of any of the Notes
(subject to extension pursuant to Sections 2(d) hereof) (the "EFFECTIVENESS
PERIOD"), or such shorter period ending when there cease to be any Transfer
Restricted Securities outstanding.

          (b) SUPPLEMENTS AND AMENDMENTS. The Company shall use its reasonable
best efforts to keep the Shelf Registration Statement continuously effective by
supplementing and amending the Shelf Registration Statement if required by the
rules, regulations or instructions applicable to the registration form used for
the Shelf Registration Statement, if required by the Securities Act or if
reasonably requested by the Holders of a majority in aggregate principal amount
of the Transfer Restricted Securities or by any underwriter of such Transfer
Restricted Securities; provided, however, that the Effectiveness Period shall be
extended as provided in Section 2(d) hereof.

          (c) SELLING SECURITYHOLDER INFORMATION. Each Holder of Transfer
Restricted Securities agrees that if such Holder wishes to sell Transfer
Restricted Securities pursuant to the Shelf Registration Statement and related
Prospectus, it will do so only in accordance with this Section 2. Each Holder of
Transfer Restricted Securities wishing to sell Transfer Restricted Securities
pursuant to the Shelf Registration Statement and related Prospectus agrees to
deliver a Notice and Questionnaire that includes such information regarding the
distribution of its Transfer Restricted Securities as is required by law to be
disclosed by the Holder in the Shelf Registration Statement (the "REQUISITE
INFORMATION") to the Company prior to any intended distribution of


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Transfer Restricted Securities under the Shelf Registration Statement and within
10 days of any request for such information from the Company (but such 10 day
requirement shall only apply to any Holder who holds Transfer Restricted
Securities on the date such request is made and at the end of the 10 day
period). From and after the date the Shelf Registration Statement becomes
effective, the Company shall, as promptly as is practicable after the date a
Notice and Questionnaire is delivered, and in any event within ten (10) Business
Days after such date, (i) if required by applicable law, file with the SEC a
post-effective amendment to the Shelf Registration Statement or prepare and, if
required by applicable law, file a supplement to the related Prospectus or a
supplement or amendment to any document incorporated therein by reference or
file any other required document so that the Holder delivering such Notice and
Questionnaire is named as a selling securityholder in the Shelf Registration
Statement and the related Prospectus in such a manner as to permit such Holder
to deliver such Prospectus to purchasers of the Transfer Restricted Securities
in accordance with applicable law and, if the Company shall file a
post-effective amendment to the Shelf Registration Statement, use its reasonable
best efforts to cause such post-effective amendment to be declared effective
under the Securities Act as promptly as is practicable; (ii) provide such Holder
copies of any documents filed pursuant to Section 2(c)(i); and (iii) notify such
Holder as promptly as practicable after the effectiveness under the Securities
Act of any post-effective amendment filed pursuant to Section 2(c)(i); PROVIDED,
that if such Notice and Questionnaire is delivered during a time that the use of
the Prospectus is suspended pursuant to Section 2(d), the Company shall so
inform the Holder delivering such Notice and Questionnaire and shall take the
actions set forth in clauses (i), (ii) and (iii) above upon such time the use of
the Prospectus may be resumed, PROVIDED, FURTHER, that if under applicable law
the Company has more than one option as to the type or manner of making any such
filing, it will make the required filing or filings in the manner or of a type
reasonably expected to result in the earliest availability of the Prospectus for
effecting resales of the Holder's Transfer Restricted Securities.

     Notwithstanding anything to the contrary in this Agreement, in the event
that the Company receives a comment from the SEC or its staff in connection with
the filing of the Shelf Registration Statement that (after discussions with the
SEC or its staff with respect to allowing the Company to include such Transfer
Restricted Securities for which Holders have not submitted a Notice and
Questionnaire in such Shelf Registration Statement) precludes the Company from
including such Transfer Restricted Securities in the Shelf Registration
Statement or after the date of this Agreement the SEC reports or annouces a
position to the same effect in a forum unrelated to the registration of the
Transfer Restricted Securities, the Company shall not be required to include the
Transfer Restricted Securities of such Holders that have not provided the
Company with such Requisite Information in such Registration Statement or
Prospectus Supplement filed pursuant to Rule 424(b) of the Securities Act and/or
any post effective amendment (to the extent that the SEC or its staff takes the
position that the Company may not file a post effective amendment with respect
to such Transfer Restricted Securities to add additional Holders not named
therein for which they have received the Requisite Information) to such Shelf
Registration Statement; PROVIDED, HOWEVER that the Company shall be required to
register the entire principal amount of the Notes issued in the initial private
placement (including any Notes, if any, issued pursuant to the option granted to
the Purchaser) on the cover page of the initial Shelf Registration Statement
filing. In such event, the Company shall be required to file a subsequent
Registration Statement ("Subsequent Registration


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Statement") registering the resale of the Transfer Restricted Securities of such
Holders within 60 days of the receipt by the Company of the Requisite
Information from any such Holders; PROVIDED that the Company shall not be
required to file more than one Subsequent Registration Statement during any
90-day period. The provisions of this agreement relating to the Shelf
Registration Statement shall equally apply to any Subsequent Registration
Statement, except that the provisions of Section 2(a) (other than the last
sentence thereof) and Section 3 shall not apply to any Subsequent Registration
Statement.

          If any such Registration Statement refers to any Holder by name or
otherwise as the holder of any securities of the Company, then such Holder shall
have the right to require, in the event that such reference to such Holder by
name or otherwise is not required by the Securities Act or any similar Federal
statute then in force, the deletion of the reference to such Holder in such
Registration Statement.

          (d) CERTAIN NOTICES; SUSPENSION OF SALES. Each Holder agrees by
acquisition of such Transfer Restricted Securities that, upon receipt of any
notice from the Company of the happening of any event of the kind described in
Sections 4(c)(ii), 4(c)(iii), 4(c)(v) or 4(c)(vi) hereof, such Holder will
forthwith discontinue disposition of such Transfer Restricted Securities covered
by the Registration Statement and Prospectus (other than in transactions exempt
from the registration requirements under the Securities Act) until such Holder's
receipt of the copies of the supplemented or amended Prospectus contemplated by
Sections 4(c)(i) and 4(k) hereof, or until it is advised in writing (the
"ADVICE") by the Company that the use of the applicable Prospectus may be
resumed, and, in either case, has received copies of any additional or
supplemental filings that are incorporated or deemed to be incorporated by
reference in such Prospectus. If the Company shall give any such notice, the
Effectiveness Period shall be extended by the number of days during such period
from and including the date of the giving of such notice to and including the
date when each Holder shall have received (x) the copies of the supplemented or
amended Prospectus contemplated by Sections 4(c)(i) and 4(k) hereof or (y) the
Advice, and, in either case, has received copies of any additional or
supplemental filings that are incorporated or deemed to be incorporated by
reference in such Prospectus.

          (e) MATERIAL EVENTS; SUSPENSION OF SALES. Notwithstanding the
provisions contained in this Section 2, in the event that, in the judgment of
the Company's Board of Directors, it is advisable to suspend use of the
Prospectus due to pending corporate developments, public filings with the SEC or
similar events, the Company shall promptly deliver a written certificate to each
registered Holder, the Special Counsel and the managing underwriters, if any, to
the effect that the use of the Prospectus is to be suspended until the Company
shall deliver a written notice that the use of the Prospectus may be resumed.
Thereafter, the use of the Prospectus shall be suspended, and the Company shall
not be required to maintain the effectiveness of, or amend or update the Shelf
Registration Statement, or amend or supplement the Prospectus; PROVIDED,
HOWEVER, that the Company shall only be permitted to suspend the use of the
Prospectus for a period not to exceed 90 days in any 12-month period. The
Company will use its best efforts to ensure that the use of the Prospectus may
be resumed as soon as, in the judgment of the Company's Board of Directors,
disclosure of the material relating to such pending development, filing or event
would not have a

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materially adverse effect on the Company. If the Company shall give any such
suspension notice pursuant to this Section 2(e), the Effectiveness Period shall
be extended by the number of days during such period from and including the date
of giving such notice to and including the date when each Holder shall have
received notice that use of the Prospectus may be resumed.

     3. LIQUIDATED DAMAGES

          (a) The Company and the Purchaser agree that the Holders will suffer
damages if the Company fails to fulfill its obligations pursuant to Section 2
hereof and that it would not be possible to ascertain the extent of such
damages. Accordingly, the Company hereby agrees to pay liquidated damages
("LIQUIDATED DAMAGES") under the circumstances and to the extent set forth
below:

               (i) to each Holder if the Shelf Registration Statement has not
been filed with the SEC on or prior to the Filing Date; or

               (ii) to each Holder if each Shelf Registration Statement is not
declared effective by the SEC on or prior to the applicable Effectiveness Target
Date; or

               (iii) to each Holder if the Shelf Registration Statement ceases
to be effective or usable at any time during the Effectiveness Period after the
Shelf Registration Statement has been ordered effective (without being succeeded
on the same day immediately by a post-effective amendment or supplement to the
Shelf Registration Statement that cures such failure and that is itself, in the
case of post-effective amendment, immediately declared effective) for a period
of time which shall exceed 90 days in the aggregate in any period of 365
consecutive days;

(any of the foregoing, a "REGISTRATION DEFAULT"); provided that the fact that
a Shelf Registration Statement is not usable by a particular Holder at any
given time solely as a result of the failure of such Holder to provide
Requisite Information with respect to it shall not be relevant for purposes
of clause (iii) above unless such Holder shall have provided such information
to the Company and the Company shall have failed to file an appropriate
Prospectus supplement or post-effective amendment to the Shelf Registration
Statement. In the event of any such Registration Default, the Company shall
accrue Liquidated Damages to each applicable Holder during the first 90-day
period immediately in an amount equal to $.05 per week per $1,000 principal
amount of Notes held by such Holder and, if applicable, on an equivalent
basis per share (subject to adjustment in the event of any stock split, stock
combination, stock dividends and the like) of Common Stock constituting
Transfer Restricted Securities held by such Holder for each week or portion
thereof that the Registration Default continues. The weekly rate at which
such Liquidated Damages accrue shall increase by an additional $.05 per
$1,000 principal amount of Notes and, if applicable, an equivalent amount per
week per share (subject to adjustment as set forth above) of Common Stock
constituting Transfer Restricted Securities for each subsequent continuing
90-day period following the occurrence of such Registration Default until all
Registration Defaults have been cured; PROVIDED, HOWEVER, that Liquidated
Damages shall not at any time exceed $.25 per week per $1,000 principal
amount of Notes or, as applicable, an equivalent amount per week per share
(subject to adjustment as set forth

                                      -8-
<PAGE>

above) of Common Stock constituting Transfer Restricted Securities. In no
event shall the Company be required to pay Liquidated Damages in excess of
the applicable maximum weekly amount, regardless of whether one or multiple
Registration Defaults shall exist. Following the cure of all Registration
Defaults, the accrual of Liquidated Damages shall cease (without in any way
limiting the effect of any subsequent Registration Default). A Registration
Default under clause (i) above shall be cured on the date that the applicable
Shelf Registration Statement is filed with the SEC; a Registration Default
under clause (ii) above shall be cured on the date that the applicable Shelf
Registration Statement is declared effective by the SEC; and a Registration
Default under clause (iii) above shall be cured on the date the applicable
Shelf Registration Statement is declared effective or otherwise usable.

          (b) The Company shall notify the Trustee within one Business Day after
each and every date on which a Registration Default occurs. Liquidated Damages
shall be paid by the Company to the Record Holders on each Damages Payment Date
in the same manner as interest is paid under the Indenture, in the case of the
Notes, and by mailing checks to their registered addresses in the register of
the Company for the Common Stock, in the case of shares of Common Stock;
PROVIDED, HOWEVER, that any Liquidated Damages accrued with respect to any Note
or portion thereof called for redemption on a redemption date, repurchased in
connection with a Repurchase Event (as defined in the Indenture) on a repurchase
date, or converted into shares of Common Stock on a conversion date prior to the
Damages Payment Date, shall, in any such event, be paid instead to the Holder
who submitted such Note or portion thereof for redemption, repurchase or
conversion on the applicable redemption date, repurchase date or conversion
date, as the case may be, on such date (promptly following the conversion date,
in the case of conversion of a Note).

          (c) All of the Company's obligations set forth in this Section 3 which
are unsatisfied to any extent with respect to any Transfer Restricted Securities
at the time such security ceases to be a Transfer Restricted Security shall
survive until such time as all such obligations with respect to such security
have been satisfied in full (notwithstanding the earlier termination of this
Agreement).

          (d) Any payments due and payable pursuant to this Section 3 with
respect to any Notes shall be subject to the provisions of Article IV of the
Indenture as if such payments were additional interest on the Notes.

          (e) The parties hereto agree that the Liquidated Damages provided for
in this Section 3 constitute a reasonable estimate of the damages that may be
incurred by holders of record of Transfer Restricted Securities by reason of the
failure of the Shelf Registration Statement to be filed or declared effective or
unavailable (absolutely or as a practical matter) for effecting resales of
Transfer Restricted Securities in accordance with the provisions hereof.
Notwithstanding the foregoing, the parties agree that the sole contractual
damages payable for a violation of the terms of this Agreement with respect to
which Liquidated Damages are expressly provided shall be such Liquidated
Damages. Nothing in this Section 3(e), however, shall preclude a holder of
Transfer Restricted Securities from pursuing or obtaining specific performance
or other equitable relief with respect to the Company's failure to pay
Liquidated Damages pursuant to this Agreement.

                                      -9-
<PAGE>

     4. REGISTRATION PROCEDURES. In connection with the Company's registration
obligations hereunder, the Company shall effect such registrations on the
appropriate form selected by the Company to permit the resale of Transfer
Restricted Securities in accordance with the intended method or methods of
disposition thereof, and pursuant thereto the Company shall as expeditiously as
reasonably possible:

          (a) No fewer than five Business Days prior to the initial filing of a
Registration Statement or Prospectus and no fewer than two Business Days prior
to the filing of any amendment or supplement thereto, furnish to the registered
Holders (determined as of the most recent reasonably practicable date which
shall not be more than two Business Days prior to the date such document is
personally delivered, delivered to a next-day courier, deposited in the mail or
telecopied, as the case may be), Special Counsel and the managing underwriters,
if any, copies of all such documents proposed to be filed (excluding, unless
requested, those incorporated or deemed to be incorporated by reference and then
only to the Holder who so requested) and cause the officers and directors of the
Company, counsel to the Company and independent certified public accountants to
the Company to respond to such inquiries as shall be necessary in connection
with such Registration Statement, in the opinion of Special Counsel and counsel
to such underwriters, to conduct a reasonable investigation within the meaning
of the Securities Act. The Company shall not file any such Registration
Statement or related Prospectus or any amendments or supplements thereto to
which the Holders of a majority in aggregate principal amount of the Transfer
Restricted Securities, Special Counsel, or the managing underwriters, if any,
shall reasonably object on a timely basis;

          (b) Prepare and file with the SEC such amendments, including
post-effective amendments, to each Registration Statement as may be necessary to
keep such Registration Statement continuously effective for the applicable time
period set forth in Section 2(a) hereof in case of the Shelf Registration
Statement and in case of any underwritten offering the period of distribution of
Transfer Restricted Securities covered by such Registration Statement; cause the
related Prospectus to be supplemented by any required Prospectus supplement, and
as so supplemented to be filed pursuant to Rule 424 under the Securities Act
with respect to the disposition of all securities covered by such Registration
Statement during such period in accordance with the intended method or methods
of disposition by the Holder set forth in such Registration Statement as so
amended or in such Prospectus as so supplemented (including, without limitation,
if permitted by the SEC, the filing of any Prospectus supplement pursuant to
Rule 424 or any post-effective amendment, in order to add or change any selling
security holder information (including any such supplements or amendments
pursuant to Section 2(c) hereof, PROVIDED such Holder to which such change
applies complies with the Requisite Information requirements of Section 2(c)
hereof));

          (c) Notify the registered (as of the most recent reasonably
practicable date which shall not be more than two Business Days prior to the
date such notice is personally delivered, delivered to a next-day courier,
deposited in the mail or telecopied, as the case may be) Holders, Special
Counsel and the managing underwriters, if any, promptly (and in the case of an
event specified by clause (i)(A) of this paragraph in no event fewer than two
Business Days prior to such filing), and (if requested by any such person),
confirm such notice in writing, (i)(A) when a


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Prospectus or any Prospectus supplement or post-effective amendment is proposed
to be filed, and, (B) with respect to a Registration Statement or any
post-effective amendment, when the same has become effective, (ii) of any
request of the SEC or any other Federal or state governmental authority for
amendments or supplements to such Registration Statement or related Prospectus
or for additional information related thereto, (iii) of the issuance by the SEC,
any state securities commission, any other governmental agency or any court of
any stop order, order or injunction suspending or enjoining the use or the
effectiveness of the Registration Statement or the initiation of any proceedings
for that purpose, (iv) if at any time any of the representations and warranties
of the Company contained in any agreement (including any underwriting agreement)
contemplated by Section 4(m) hereof are not true and correct in all material
respects when made during the effectiveness of such agreement, (v) of the
receipt by the Company of any notification with respect to the suspension of the
qualification or exemption from qualification of any of the Transfer Restricted
Securities for sale in any jurisdiction, or the initiation or threatening of any
proceeding for such purpose, and (vi) of the existence of any fact and the
happening of any event that makes any statement made in such Registration
Statement or related Prospectus untrue in any material respect, or that requires
the making of any changes in such Registration Statement or Prospectus so that
in the case of the Registration Statement, it will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading and
that, in the case of the Prospectus, such Prospectus will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading;

          (d) Use its reasonable best efforts to avoid the issuance of, or, if
issued, obtain the withdrawal of any stop order or order enjoining or suspending
the use or effectiveness of a Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Transfer Restricted Securities for sale in any jurisdiction, at the earliest
practicable moment;

          (e) If requested by the Special Counsel, the managing underwriters, if
any, or the Holders of a majority in aggregate principal amount of the Transfer
Restricted Securities being sold in connection with such offering, (i) promptly
include in a Prospectus supplement or post-effective amendment such information
as the Special Counsel, the managing underwriters, if any, and such Holders
agree should, in their reasonable judgment, be included therein, and (ii) make
all required filings of such Prospectus supplement or such post-effective
amendment as soon as reasonably practicable after the Company has received
notification of the matters to be included in such Prospectus supplement or
post-effective amendment; PROVIDED, HOWEVER, that the Company shall not be
required to take any action pursuant to this Section 4(e) that would, in the
opinion of counsel for the Company, violate applicable law or which is not
reasonably required to comply with applicable securities laws;

          (f) Furnish to each Holder who so requests, Special Counsel and each
managing underwriter, if any, without charge, at least one conformed copy of
each Registration Statement and each amendment thereto, including financial
statements (but excluding schedules, all documents


                                      -11-
<PAGE>

incorporated or deemed to be incorporated therein by reference and all exhibits,
unless requested in writing by such Holder, Special Counsel or managing
underwriter);

          (g) Deliver to each Holder, the Special Counsel, and the underwriters,
if any, without charge, as many copies of the Prospectus or Prospectuses
(including each form of Prospectus) and each amendment or supplement thereto as
such persons may reasonably request; and, unless the Company shall have given
notice to such Holder pursuant to Section 4(c), the Company hereby consents to
the use of such Prospectus and each amendment or supplement thereto by each of
the selling Holders of Transfer Restricted Securities and the underwriters, if
any, in connection with the offering and sale of the Transfer Restricted
Securities covered by such Prospectus and any amendment or supplement thereto,
PROVIDED, HOWEVER, that no Holder shall be entitled to use the Prospectus unless
and until such Holder shall have furnished to the Company any and all Requisite
Information pursuant to Section 2(c) hereof;

          (h) Use its reasonable best efforts to register or qualify, or
cooperate with the Holders of Transfer Restricted Securities to be sold or
tendered for, the underwriters, if any, and their respective counsel in
connection with the registration or qualification (or exemption from such
registration or qualification) of, such Transfer Restricted Securities for offer
and sale under the securities or Blue Sky laws of such jurisdictions within the
United States as any Holder or underwriter reasonably requests in writing, keep
each such registration or qualification (or exemption therefrom) effective
during the period such Registration Statement is required to be kept effective
and do any and all other acts or things necessary legally to enable the
disposition in such jurisdictions of the Transfer Restricted Securities covered
by the applicable Registration Statement; PROVIDED, HOWEVER, that the Company
shall not be required to qualify generally to do business in any jurisdiction
where it is not then so qualified, take any action that would subject it to
general service of process in any such jurisdiction where it is not then so
subject or subject the Company to any tax in any such jurisdiction where it is
not then so subject;

          (i) In connection with any sale or transfer of Transfer Restricted
Securities that will result in such securities no longer being Transfer
Restricted Securities, cooperate with the Holders and the managing underwriters,
if any, to (A) facilitate the timely preparation and delivery of certificates
representing Transfer Restricted Securities to be sold, which certificates shall
not bear any restrictive legends, for the Notes shall bear a CUSIP number
different from the CUSIP number for the Transfer Restricted Securities and for
any Transfer Restricted Securities shall be in a form eligible for deposit with
The Depository Trust Company and (B) enable such Transfer Restricted Securities
to be in such denominations and registered in such names as the managing
underwriters, if any, or Holders may reasonably request at least two Business
Days prior to any sale of Transfer Restricted Securities;

          (j) Use its reasonable best efforts to cause the offering of the
Transfer Restricted Securities covered by the Registration Statement to be
registered with or approved by such other governmental agencies or authorities
within the United States, except as may be reasonably required as a consequence
of the nature of a Holder's business, in which case the Company will cooperate
in all reasonable respects with the filing of such Registration Statement and
the granting of such approvals as may be reasonably necessary to enable the
seller or sellers thereof or the underwriters, if


                                      -12-
<PAGE>


any, to consummate the disposition of such Transfer Restricted Securities;
PROVIDED, HOWEVER, that the Company shall not be required to register the
Transfer Restricted Securities in any jurisdiction that would require the
Company to qualify to do business in any jurisdiction where it is not then so
qualified, subject it to general service of process in any such jurisdiction
where it is not then so subject or subject the Company to any tax in any such
jurisdiction where it is not then so subject or to;

          (k) Upon the occurrence of any event contemplated by Section 4(c)(vi)
hereof, as promptly as reasonably practicable, prepare a supplement or
amendment, including, if appropriate, a post-effective amendment, to each
Registration Statement or a supplement to the related Prospectus or any document
incorporated or deemed to be incorporated therein by reference, and file any
other required document so that, as thereafter delivered, such Prospectus will
not contain an 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 under which they were made, not misleading;

          (l) Prior to the effective date of the first Registration Statement
relating to the Transfer Restricted Securities, to provide a CUSIP number for
the Transfer Restricted Securities to be sold pursuant to the Registration
Statement;

          (m) Enter into such agreements (including an underwriting agreement in
form, scope and substance as are customary in underwritten offerings) reasonably
satisfactory to the Company and take all such other reasonable actions in
connection therewith (including those reasonably requested by the managing
underwriters, if any, or the Holders of a majority in aggregate principal amount
of the Transfer Restricted Securities being sold) in order to expedite or
facilitate the sale of such Transfer Restricted Securities; PROVIDED, HOWEVER,
that the Company is required to facilitate no more than one underwritten
offering. In such connection, whether or not an underwriting agreement is
entered into and whether or not the registration is an underwritten
registration, (i) make such representations and warranties to the Holders of
such Transfer Restricted Securities and the underwriters, if any, with respect
to the business of the Company and its subsidiaries (including with respect to
businesses or assets acquired or to be acquired by any of them), and the
Registration Statement, Prospectus and documents, if any, incorporated or deemed
to be incorporated by reference therein, in each case, in form, substance and
scope as are customarily made by issuers to underwriters in underwritten
offerings and reasonably acceptable to the Company, and confirm the same if and
when requested; (ii) seek to obtain opinions of counsel to the Company and
updates thereof (which counsel and opinions (in form, scope and substance) shall
be reasonably satisfactory to the managing underwriters, if any, and Special
Counsel to the Holders of the Transfer Restricted Securities being sold,
addressed to each selling Holder of Transfer Restricted Securities and each of
the underwriters, if any, covering the matters customarily covered in opinions
requested in underwritten offerings (including any such matters as may be
reasonably requested by such Special Counsel and underwriters); (iii) use all
reasonable efforts to obtain customary "cold comfort" letters and updates
thereof from the independent certified public accountants of the Company (and,
if necessary, any other independent certified public accountants of any
subsidiary of the Company or of any business acquired by the Company for which
financial statements and financial data is, or is


                                      -13-
<PAGE>


required to be, included in the Registration Statement), addressed (where
reasonably possible) to each selling Holder of Transfer Restricted Securities
and each of the underwriters, if any, such letters to be in customary form and
covering matters of the type customarily covered in "cold comfort" letters in
connection with underwritten offerings; (iv) if an underwriting agreement is
entered into, the same shall contain indemnification provisions and procedures
no less favorable to the selling Holders of Transfer Restricted Securities and
the underwriters, if any, than those set forth in Section 6 hereof (or such
other customary provisions and procedures acceptable to Holders of a majority in
aggregate principal amount of the Transfer Restricted Securities covered by such
Registration Statement and the managing underwriters); and (v) deliver such
documents and certificates as may be reasonably requested by the Holders of
majority in aggregate principal amount of the Transfer Restricted Securities
being sold, their Special Counsel or the managing underwriters, if any, to
evidence the continued validity of the representations and warranties made
pursuant to clause (i) of this Section 4(m) and to evidence compliance with any
customary conditions contained in the underwriting agreement or other agreement
entered into by the Company;

          (n) Make available for inspection by any one representative of the
Holders of Transfer Restricted Securities being sold, any underwriter
participating in any such disposition of Transfer Restricted Securities, if any,
and any one law firm or accounting firm retained by such selling Holders or
underwriter, at the offices where normally kept, during reasonable business
hours, all financial and other records, pertinent corporate documents and
properties of the Company and its subsidiaries as they may reasonably request,
and cause the officers, directors, agents and employees of the Company and its
subsidiaries to supply all information in each case reasonably requested by any
such representative, underwriter, law firm or accounting firm in connection with
such Registration Statement, PROVIDED, HOWEVER, that such persons shall first
agree in writing with the Company that any information that is reasonably and in
good faith designated by the Company in writing as confidential at the time of
delivery or inspection (as the case may be) of such information shall be kept
confidential by such persons, unless (i) disclosure of such information is
required by court or administrative order or is necessary to respond to
inquiries of regulatory authorities, (ii) disclosure of such information is
required by law (including any disclosure requirements pursuant to Federal
securities laws in connection with the filing of any Registration Statement or
the use of any Prospectus); provided that the Holders will cooperate with the
Company to enable the Company to seek a protective order, confidential treatment
or otherwise attempt to protect the confidential information, (iii) such
information becomes generally available to the public other than as a result of
a disclosure or failure to safeguard by any such person or (iv) such information
becomes available to any such person from a source other than the Company and
such source is not bound by a confidentiality agreement.

          (o) Use its reasonable best efforts to cause the Indenture to be
qualified under the TIA not later than the effective date of the first
Registration Statement relating to the Transfer Restricted Securities; and in
connection therewith, cooperate with the Trustee and the Holders of Notes
constituting Transfer Restricted Securities to effect such changes to the
Indenture, if any, as may be required for such Indenture to be so qualified in
accordance with the terms of the TIA; and execute, and use its best efforts to
cause the Trustee to execute, all customary documents as may be

                                      -14-
<PAGE>


required to effect such changes, and all other forms and documents (including
Form T-1) required to be filed with the SEC to enable the Indenture to be so
qualified under the TIA in a timely manner.

          (p) Comply with applicable rules and regulations of the SEC and make
generally available to its security holders earning statements satisfying the
provisions of Section 11(a) of the Securities Act or Rule 158 of the Securities
Act (or any similar rule promulgated under the Securities Act), no later than 45
days after the end of any 12-month period (or 90 days after the end of any
12-month period if such period is a fiscal year) (i) commencing at the end of
any fiscal quarter in which Transfer Restricted Securities are sold to
underwriters in a firm commitment or best efforts underwritten offering and (ii)
if not sold to underwriters in such an offering, commencing on the first day of
the first fiscal quarter after the effective date of a Registration Statement,
which statement shall cover said period, consistent with the requirements of
Rule 158 of the Securities Act; and

          (q) (i) list all shares of Common Stock covered by such Registration
Statement on any securities exchange on which the Common Stock is then listed or
(ii) if required by the applicable rules, authorize for quotation on the
National Association of Securities Dealers Automated Quotation System ("NASDAQ")
or the National Market of Nasdaq all Common Stock covered by such Registration
Statement if the Common Stock is then so authorized for quotation.

     5. REGISTRATION EXPENSES

          (a) All fees and expenses incident to the performance of or compliance
with this Agreement by the Company shall be borne by it whether or not any
Registration Statement is filed or becomes effective and whether or not any
securities are offered or sold pursuant to any Registration Statement. The fees
and expenses referred to in the foregoing sentence shall include, without
limitation, (i) all registration and filings fees (including, without
limitation, fees and expenses (A) with respect to filings required to be made
with the National Association of Securities Dealers, Inc. and (B) in compliance
with securities or Blue Sky laws (including, without limitation and in addition
to that provided for in (b) below, fees and disbursements of counsel for the
underwriters or the Special Counsel in connection with Blue Sky qualifications
of the Transfer Restricted Securities and determination of the eligibility of
the Transfer Restricted Securities for investment under the laws of such
jurisdictions as the managing underwriters, if any, or Holders of a majority in
aggregate principal amount of Transfer Restricted Securities, may designate)),
(ii) printing expenses (including, without limitation, expenses of printing
certificates for Transfer Restricted Securities in a form eligible for deposit
with The Depository Trust Company and of printing Prospectuses if the printing
of Prospectuses is required by the managing underwriters, if any, or by the
Holders of a majority in aggregate principal amount of the Transfer Restricted
Securities included), (iii) messenger, telephone and delivery expenses of the
Company, (iv) fees and disbursements of counsel for the Company and the
reasonable fees and expenses of Special Counsel (plus any local counsel
reasonably deemed appropriate by the Holders of a majority in aggregate
principal amount of the Transfer Restricted Securities) in accordance with the
provisions of Section 5(b) hereof, (v) fees and disbursements of all independent
certified public accountants referred to in Section 4(m)(iii) (including,
without limitation, the expenses of any special audit and "comfort" letters
required by or incident to such performance), (vi) Securities Act liability
insurance, if the Company so desires such insurance, and (vii) fees and expenses
of all other persons retained by the Company. In addition, the Company shall

                                      -15-
<PAGE>

pay its internal expenses (including, without limitation, all salaries and
expenses of its officers and employees performing legal or accounting duties),
the expense of an annual audit and the fees and expenses incurred in connection
with the listing of the securities to be registered on any securities exchange
or the Nasdaq National Market. Notwithstanding anything in this Agreement to the
contrary, each Holder shall pay all underwriting discounts and brokerage
commissions with respect to any Transfer Restricted Securities sold by it.

          (b) In connection with any registration hereunder, the Company shall
reimburse the Holders of the Transfer Restricted Securities being registered or
tendered for in such registration for the reasonable fees and disbursements of
not more than one firm of attorneys representing the selling Holders (in
addition to any local counsel), which firm shall initially be chosen by the
Holders of a majority in aggregate principal amount of the Transfer Restricted
Securities. Wilson Sonsini Goodrich & Rosati, P.C. shall be Special Counsel for
all purposes hereof, but which may, with the written consent of the Purchaser
(which shall not be unreasonably withheld), be another nationally recognized law
firm experienced in securities law matters designated by the Company unless and
until another Special Counsel shall have been selected by a majority in
aggregate principal amount of the Transfer Restricted Securities and notice
hereof shall have been given to the Company.

     6. INDEMNIFICATION

          (a) The Company agrees to indemnify and hold harmless (i) the
Purchaser, (ii) each Holder, (iii) each person, if any, who controls (within the
meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act)
any of the foregoing (any of the persons referred to in this clause (iii) being
hereinafter referred to as a "CONTROLLING PERSON"), and (iv) the respective
officers, directors, partners, employees, representatives and agents of the
Purchaser, the Holders (including predecessor Holders), or any Controlling
Person (any person referred to in clause (i), (ii), (iii) or (iv) may
hereinafter be referred to as an "INDEMNIFIED PERSON"), from and against any and
all losses, claims, damages, liabilities, expenses and judgments caused by any
untrue statement or alleged untrue statement of a material fact contained in any
Registration Statement or Prospectus or in any amendment or supplement thereto
or in any preliminary Prospectus, or caused by any omission or alleged omission
to state therein a material fact required to be stated therein or necessary to
make the statements therein (in the case of any Prospectus or supplement
thereto, in light of the circumstances under which they were made) not
misleading, except insofar as such losses, claims, damages, liabilities,
expenses or judgments are caused by any such untrue statement or omission or
alleged untrue statement or omission based upon information relating to any
Indemnified Person furnished to the Company by or on behalf of such Indemnified
Person expressly for use therein; PROVIDED, HOWEVER, that the foregoing
indemnity with respect to any preliminary Prospectus shall not inure to the
benefit of any Indemnified Person from whom the person asserting such losses,
claims, damages, liabilities, expenses and judgments purchased securities if
such untrue statement or omission or alleged untrue statement or omission made
in such preliminary Prospectus is eliminated or remedied in the Prospectus and a
copy of the Prospectus shall not have been furnished to such person in a timely
manner due to the wrongful action or wrongful inaction of such Indemnified
Person, whether as a result of negligence or otherwise.

                                      -16-
<PAGE>

          (b) In case any action shall be brought against any Indemnified
Person, based upon any Registration Statement or any such Prospectus or any
amendment or supplement thereto and with respect to which indemnity may be
sought against the Company, such Indemnified Person shall promptly notify the
Company in writing and the Company shall assume the defense thereof, including
the employment of counsel reasonably satisfactory to such Indemnified Person and
payment of all fees and expenses. Any Indemnified Person shall have the right to
employ separate counsel in any such action and participate in the defense
thereof, but the fees and expenses of such counsel shall be at the expense of
such Indemnified Person, unless (i) the employment of such counsel shall have
been specifically authorized in writing by the Company, (ii) the Company shall
have failed to assume the defense and employ counsel or (iii) such Indemnified
Person or Persons shall have been advised by counsel that there may be a
conflict between the positions of the indemnifying party or parties and of the
indemnified party or parties in conducting the defense of such action or
proceeding or that there may be legal defenses available to such Indemnified
Person or Persons different from or in addition to those available to the
indemnifying party or parties (in which case the Company shall not have the
right to assume the defense of such action on behalf of such Indemnified
Person), it being understood, however, that the Company shall not, in connection
with any one such action or separate but substantially similar or related
actions in the same jurisdiction arising out of the same general allegations or
circumstances, be liable for the fees and expenses of more than one separate
firm of attorneys (in addition to any local counsel) for all such Indemnified
Persons, which firm shall be designated in writing by such Indemnified Persons,
and that all such fees and expenses shall be reimbursed as they are incurred.
The Company shall not be liable for any settlement of any such action effected
without its written consent but if settled with the written consent of the
Company, the Company agrees to indemnify and hold harmless, in accordance with
this Section 6, any Indemnified Person from and against any loss or liability by
reason of such settlement. No Indemnifying Party shall, without the prior
written consent of the Indemnified Party, effect any settlement of any pending
or threatened proceeding in respect of which any Indemnified Party is or could
have been a party and indemnity could have been sought hereunder by such
Indemnified Party, unless such settlement includes an unconditional release of
such Indemnified Party from all liability on claims that are the subject matter
of such proceeding.

          (c) In connection with any Registration Statement pursuant to which
any Holder (or predecessor Holder) sold or offered for resale Transfer
Restricted Securities, such Holder (or predecessor Holder) agrees, severally and
not jointly, to indemnify and hold harmless the Company, its directors, its
officers, employees, representatives, agents and any person controlling the
Company within the meaning of Section 15 of the Securities Act or Section 20 of
the Exchange Act (any such person referred to as a "COMPANY INDEMNIFIED PERSON"
and collectively with the Indemnified Persons, any such person referred to as an
"INDEMNIFIED PARTY"), to the same extent as the foregoing indemnity from the
Company to each Indemnified Person but only with reference to information
relating to such Indemnified Person furnished by or on behalf of such
Indemnified Person expressly for use in such Registration Statement. In case any
action shall be brought against any Company Indemnified Person, based on such
Registration Statement and in respect of which indemnity may be sought against
any Indemnifying Party, the Indemnifying Party shall have the rights and duties
given to the Company (except that if the Company shall have assumed the defense
thereof, such Indemnifying Party shall not be required to do so, but may employ
separate counsel therein and


                                      -17-
<PAGE>

participate in defense thereof but the fees and expenses of such counsel shall
be at the expense of such Indemnifying Party), and the Company Indemnified
Person shall have the rights and duties given to the Indemnified Person by
Section 6(b) hereof.

          (d) If the indemnification provided for in this Section 6 is
unavailable to an Indemnified Party in respect of any losses, claims, damages,
liabilities, expenses or judgments referred to therein, then each Indemnifying
Party, in lieu of indemnifying such Indemnified Party, shall contribute to the
amount paid or payable by such Indemnified Party as a result of such losses,
claims, damages, liabilities, expenses and judgments (i) in such proportion as
is appropriate to reflect the relative benefits received by the Company on the
one hand and each Indemnified Person on the other hand pursuant to the Purchase
Agreement or from the offering for resale of the Transfer Restricted Securities
or (ii) if the allocation provided by clause (i) above is not permitted by
applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause (i) above but also the relative fault of
the Company and each such Indemnified Person in connection with the statements
or omissions which resulted in such losses, claims, damages, liabilities,
expenses or judgments, as well as any other relevant equitable considerations.
The relative fault of the Company and each such Indemnified Person shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of a material fact or the omission to state a material fact
relates to information supplied by the Company or such Indemnified Person and
the parties' relative intent, knowledge, access to information and opportunity
to correct or prevent such statement or omission.

          The Company, the Holders and the Purchaser agree that it would not be
just and equitable if contribution pursuant to this Section 6(d) were determined
by PRO RATA allocation (even if the Indemnified Person were treated as one
entity for such purpose) or by any other method of allocation which does not
take account of the equitable considerations referred to in the immediately
preceding paragraph. The amount paid or payable by an Indemnified Party as a
result of the losses, claims, damages, liabilities, expenses or judgments
referred to in the immediately preceding paragraph shall be deemed to include,
subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such Indemnified Party in connection with investigating
or defending any such action or claim. Notwithstanding the provisions of this
Section 6, no Indemnified Person shall be required to contribute any amount in
excess of the amount by which the total net profit received by it in connection
with the sale of the Transfer Restricted Securities pursuant to this Agreement
exceeds the amount of any damages which such Indemnified Person has otherwise
been required to pay by reason of such untrue or alleged untrue statement or
omission or alleged omission. No person guilty of fraudulent misrepresentation
(within the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. The Indemnified Persons' obligations to contribute pursuant
to this Section 6(d) are several in proportion to the respective amount of
Transfer Restricted Securities included in and sold pursuant to any such
Registration Statement by each Indemnified Person and not joint.


                                      -18-
<PAGE>



     7. RULES 144 AND 144A

          The Company shall file the reports required to be filed by it under
the Securities Act and the Exchange Act in a timely manner and, if at any time
it is not required to file such reports but in the past had been required to or
did file such reports, it will, upon the request of any Holder, make available
other information as required by, and so long as necessary to permit sales of,
its Transfer Restricted Securities pursuant to Rule 144 and Rule 144A.
Notwithstanding the foregoing, nothing in this Section 7 shall be deemed to
require the Company to register any of its securities pursuant to the Exchange

     Act. 8. UNDERWRITTEN REGISTRATIONS

          If any of the Transfer Restricted Securities covered by the Shelf
Registration Statement are to be sold in an underwritten offering, the
investment banker or investment bankers and manager or managers that will
administer the offering will be investment bankers of recognized national
standing selected by the Holders of a majority in aggregate principal amount of
such the Notes (or the proportional amount of Common Stock held as Transfer
Restricted Securities) included in such offering, subject to the consent of the
Company (which will not be unreasonably withheld or delayed).

          No person may participate in any underwritten registration hereunder
unless such person (i) agrees to sell such person's Transfer Restricted
Securities on the basis reasonably provided in any underwriting arrangements
approved by the persons entitled hereunder to approve such arrangements and (ii)
completes and executes all questionnaires, powers of attorney, indemnities
underwriting agreements, lock-up agreements and other documents reasonably
required under the terms of such underwriting arrangements.

     9. MISCELLANEOUS

          (a) REMEDIES. In the event of a breach by the Company or by a Holder
of any of their respective obligations under this Agreement, each Holder or the
Company, in addition to being entitled to exercise all rights granted by law,
including, without limitation, recovery of damages, will be entitled to specific
performance of its rights under this Agreement. The Company and each Holder
agree that monetary damages would not be adequate compensation for any loss
incurred by reason of a breach by it of any of the provisions of this Agreement
and hereby further agree that, in the event of any action for specific
performance in respect of such breach, they shall waive the defense that a
remedy at law would be adequate. This Section 9(a) shall not apply to Section 3.

          (b) NO INCONSISTENT AGREEMENTS. The Company shall not enter into any
agreement with respect to its securities that is inconsistent with the rights
granted to the Holders in this Agreement or otherwise conflicts with the
provisions hereof. The Company is not currently a party to any agreement
granting any registration rights with respect to any of its securities to any
person which conflicts with the Company's obligations hereunder or gives any
other party the right to include any securities in any Registration Statement
filed pursuant hereto, except for such rights and conflicts as have been
irrevocably waived. Without limiting the generality of the foregoing until


                                      -19-
<PAGE>


the date at which the Securities (as defined in the Purchase Agreement) cease to
be Transfer Restricted Securities, without the written consent of the Holders of
a majority in aggregate principal amount of the Transfer Restricted Securities,
the Company shall not grant to any person the right to request it to register
any of its securities under the Securities Act unless the rights so granted are
subject in all respect to the prior rights of the Holders set forth herein, and
are not otherwise in conflict or inconsistent with the provisions of this
Agreement.

          (c) NO ADVERSE ACTION AFFECTING THE TRANSFER RESTRICTED SECURITIES.
The Company will not take any action with respect to the Transfer Restricted
Securities which would adversely affect the ability of any of the Holders to
include such Transfer Restricted Securities in a registration undertaken
pursuant to this Agreement.

          (d) NO PIGGYBACK ON FIRST REGISTRATION. After the date hereof, the
Company shall not grant to any of its security holders (other than the Holders
in such capacity) the right to include any of its securities in the initial
Shelf Registration Statement.

          (e) AMENDMENTS AND WAIVERS. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof,
may not be given, without the written consent of the Holders of a majority in
aggregate principal amount of the Transfer Restricted Securities; PROVIDED,
HOWEVER, that, for the purposes of this Agreement, Transfer Restricted
Securities that are owned, directly or indirectly, by either the Company or an
Affiliate of the Company are not deemed outstanding. Notwithstanding the
foregoing, a waiver or consent to depart from the provisions hereof with respect
to a matter that relates exclusively to the rights of Holders whose Transfer
Restricted Securities are being sold pursuant to an underwritten offering and
that does not directly or indirectly affect the rights of other Holders may be
given by Holders of a majority in aggregate principal amount of the Transfer
Restricted Securities being sold by such Holders pursuant to such an
underwritten offering; PROVIDED, HOWEVER, that the provisions of this sentence
may not be amended, modified, or supplemented except in accordance with the
provisions of the immediately preceding sentence.

          (f) NOTICES. All notices and other communications provided for herein
shall be made in writing by hand-delivery, next day air courier, certified
first-class mail, return receipt requested or telecopy; provided a copy of any
such telecopy is immediately followed up by next day courier:

               (i)  if to a Holder, to the address of such Holder as it appears
                    in the Note or Common Stock register of the Company, as
                    applicable;

               (ii) if to the Company, to:
                    Sepracor, Inc.
                    111 Locke Drive
                    Marlborough, MA 01752
                    Attn: Robert F. Scumaci
                    Telecopy No.:(508) 357-7479


                                      -20-
<PAGE>


                    with a copy to:
                    Hale and Dorr, LLP
                    60 State Street
                    Boston, MA  02109
                    Attn:  Susan W. Murley
                    Telecopy No.: (617) 526-5000

               (iii) if to the Special Counsel, to:

                     Wilson Sonsini Goodrich & Rosati, P.C.
                     650 Page Mill Road
                     Palo Alto, CA  94304
                     Attn:  John A. Fore, Esq.
                     Telecopy No.: (650) 845-5000

or such other Special Counsel at such other address and telecopy number as a
majority in aggregate principal amount of the Transfer Restricted Securities
shall have given notice to the Company as contemplated by Section 5(b) hereof.

          Except as otherwise provided in this Agreement, all such
communications shall be deemed to have been duly given, when delivered by hand,
if personally delivered; one Business Day after being timely delivered to a
next-day air courier, five Business Days after being deposited in the mail,
postage prepaid, if mailed; and when receipt is acknowledged by the recipient's
telecopier machine, if telecopied; provided a copy of any such telecopy is
immediately followed up by next day courier.

          (g) SUCCESSORS AND ASSIGNS. This Agreement shall inure to the benefit
of and be binding upon the successors and permitted assigns of each of the
parties and shall inure to the benefit of each existing and future Holder. The
Company may not assign its rights or obligations hereunder without the prior
written consent of the Holders of a majority in aggregate principal amount of
the Transfer Restricted Securities, other than by operation of law pursuant to a
merger or consolidation to which the Company is a party. In the event the Notes
constituting Transfer Restricted Securities become convertible into common stock
of another person pursuant to Section 15.6 of the Indenture, the Company shall
cause such person to assume the Company's obligations hereunder.

          (h) COUNTERPARTS. This Agreement may be executed in any number of
counterparts by the parties hereto, 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 instrument.

          (i) GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, AS APPLIED TO CONTRACTS
MADE AND PERFORMED WITHIN THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW.

                                      -21-
<PAGE>


          (j) SEVERABILITY. The remedies provided herein are cumulative and not
exclusive of any remedies provided by law. If any term, provision, covenant or
restriction of this Agreement is held by a court of competent jurisdiction to be
invalid, illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their best efforts to find and employ an alternative means to
achieve the same or substantially the same result as that contemplated by such
term, provision, covenant or restriction. It is hereby stipulated and declared
to be the intention of the parties that they would have executed the remaining
terms, provisions, covenants and restrictions without including any of such that
may be hereafter declared invalid, illegal, void or unenforceable.

          (k) HEADINGS. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof. All
references made in this Agreement to "Section" and "paragraph" refer to such
Section or paragraph of this Agreement, unless expressly stated otherwise.

          (l) ATTORNEYS' FEES. In any action or proceeding brought to enforce
any provision of this Agreement, or where any provision hereof is validly
asserted as a defense, the prevailing party, as determined by the court, shall
be entitled to recover its reasonable attorneys' fees in addition to any other
available remedy.


                                      -22-
<PAGE>





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

                                    SEPRACOR INC.

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

                                    Name:
                                         --------------------------------------

                                    Title:
                                          -------------------------------------




The foregoing Registration Rights Agreement
is hereby confirmed and agreed to as of the
date first written above:

ROBERTSON STEPHENS, INC.



By:
  -------------------------
  Authorized Signatory