Document:

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                           STAND-BY PURCHASE AGREEMENT

                                     BETWEEN

                            RAMIUS CAPITAL GROUP, LLC

                                       AND

                         TRIANGLE PHARMACEUTICALS, INC.

                                November 1, 2000

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PROVISIONAL PATENT APPLICATION HAS BEEN FILED
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                                TABLE OF CONTENTS

                                                                           Page

I.    DEFINITIONS............................................................1

II.   PURCHASE AND SALE OF COMMON STOCK......................................2
      2.1   Investments......................................................2
      2.2   Limitations on Investment Amount.................................2
      2.3   Closings and Settlements.........................................2
      2.4   Termination, Suspension and Modification of Investment
            Obligation ......................................................3

III.  CONDITIONS PRECEDENT...................................................3
      3.1   Conditions Precedent to the Obligation of the Investor to
            Purchase Common Stock Pursuant to a Capital Demand Notice........3
      3.2   Occurrence of Material Events....................................3
      3.3   Due Diligence Review.............................................4

IV.   REPRESENTATIONS AND WARRANTIES OF INVESTOR.............................4
      4.1   Authorization; Enforcement.......................................4
      4.2   Not an Affiliate.................................................4
      4.3   Organization and Standing........................................4
      4.4   Absence of Conflicts.............................................4

V.    REPRESENTATIONS AND WARRANTIES OF THE COMPANY..........................5

VI.   COVENANTS..............................................................5
      6.1   Short Selling....................................................5

VII.  ASSIGNMENT, ENTIRE AGREEMENT, AMENDMENT, TERMINATION...................5
      7.1   Successors and Assigns...........................................5
      7.2   Entire Agreement; Amendment......................................5
      7.3   Publicity........................................................5
      7.4   Termination......................................................5

VIII. NOTICES; COSTS AND EXPENSES............................................6
      8.1   Notices..........................................................6
      8.2   Costs and Expenses...............................................7

IX.   INDEMNIFICATION AND CONTRIBUTION.......................................8
      9.1   Indemnification..................................................8
      9.2   Contribution....................................................10

X.    GOVERNING LAW; MISCELLANEOUS..........................................10
      10.1  Governing Law...................................................10
      10.2  Counterparts....................................................10
      10.3  Headings........................................................10
      10.4  Severability....................................................10
      10.5  Survival........................................................11
      10.6  No Third Party Beneficiaries....................................11
      10.7  Further Assurances..............................................11

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      10.8  Construction....................................................11
      10.9  Equitable Relief................................................11
      10.10 Consent to Jurisdiction.........................................11

                         List of Exhibits and Schedules

Notice of Blocking Period                             Exhibit 3.2

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                                CROSS REFERENCES

Defined Term
------------

"Advice"                                                       Section 3.2
"Agreement"                                                    Preamble
"Blocking Event"                                               Section 2.4
"Buy-In Actual Damages"                                        Section 2.3
"Claims"                                                       Section 9.1(a)
"Closing Date"                                                 Section 1
"Common Stock"                                                 Recitals
"Company"                                                      Preamble
"Condition Precedent Date"                                     Section 3.1
"DTC"                                                          Section 2.3(a)
"Indemnified Damages"                                          Section 9.1(a)
"Indemnified Party"                                            Section 9.1(b)
"Indemnified Person"                                           Section 9.1(a)
"Investor"                                                     Preamble
"Notice of Blocking Period"                                    Section 3.2
"Permitted Transferee"                                         Section 7.1
"Purchase Price"                                               Section 1
"Registrable Securities"                                       Section 1
"Registration Statement"                                       Section 2.4(a)(i)
"SEC"                                                          Section 2.4
"Settlement Date"                                              Section 1
"Underwriter"                                                  Recitals
"Underwriting Agreement"                                       Recitals
"Violations"                                                   Section 9.1(a)

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
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                           STAND-BY PURCHASE AGREEMENT

            STAND-BY PURCHASE AGREEMENT dated as of November 1, 2000 (the
"Agreement"), between Ramius Capital Group, LLC, a limited liability company
organized and existing under the laws of the State of Delaware (the "Investor"),
and Triangle Pharmaceuticals, Inc., a corporation organized and existing under
the laws of the State of Delaware (the "Company").

                              W I T N E S S E T H :

            WHEREAS, pursuant to the Common Stock Underwriting Agreement between
Ramius Securities, LLC (the "Underwriter") and the Company dated as of the date
hereof and attached hereto as Exhibit 1 (the "Underwriting Agreement"), the
Underwriter agreed to sell, as the Company's agent, on a best efforts basis, up
to $100 million of the Company's Common Stock, $.001 par value per share (the
"Common Stock");

            WHEREAS, upon the terms and subject to the conditions of this
Agreement, should the Underwriter fail to fulfill its Selling Period Obligation
then the Investor shall be obligated to purchase the number of shares of the
Company's Common Stock necessary to fulfill the Underwriter's Selling Period
Obligation;

            WHEREAS, terms used in this Agreement without being specifically
defined herein shall have the meanings set forth in the Underwriting Agreement.

            NOW, THEREFORE, the parties hereto agree as follows:

I. DEFINITIONS.

            Capitalized terms not defined herein shall have the same meaning
ascribed to them in the Underwriting Agreement. As used in this Agreement, the
following terms shall have the following meanings:

            "Closing Date" shall mean, with respect to the purchase and sale of
Common Stock subject to the conditions contained herein, the First Trading Day
following the expiration of the Selling Period if the Underwriter fails to
fulfill its Selling Period Obligation for such Selling Period.

            "Notice of Blocking Period" shall mean the notice delivered by the
Company to the Underwriter pursuant to Section 3.2, in the form attached hereto
as Exhibit 3.2.

            "Purchase Price" shall mean 95.75% of the VWAP for the first Trading
Day following the expiration of the Selling Period; provided, that if the VWAP
for such Trading Day is at or below the Hard Floor Price, the VWAP for such day
shall be deemed to be the Hard Floor Price.

            "Registrable Securities" shall mean any shares of Common Stock
issued or issuable to the Investor or any holder or transferee pursuant to this
Agreement and any shares of Capital Stock issued or issuable with respect to the
foregoing as a result of any stock split, stock dividend, recapitalization,
exchange or similar event.

            "Settlement Date" shall mean, with respect to the purchase and sale
of Common Stock, subject to the conditions contained herein, the Trading Day no
later than three days following the Closing Date.

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
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II. PURCHASE AND SALE OF COMMON STOCK.

      2.1 Investments. If pursuant to the terms and conditions of the
Underwriting Agreement, the Company delivers a Capital Demand Notice to the
Underwriter and the Underwriter fails to fulfill its Selling Period Obligation,
then the Investor, subject to the terms and conditions of this Agreement, shall
be obligated to purchase from the Company the number of shares of Common Stock
necessary to fulfill the Underwriter's Selling Period Obligation.

      2.2 Limitations on Investment Amount.

            (a) Selling Period Obligation. The Investor's obligation to purchase
shares of the Company's Common Stock shall be null and void if (i) a Blocking
Event occurs (as provided in Section 2.4); or (ii) the remaining Selling Period
Obligation multiplied by the Purchase Price is less than $50,000. The Investor
may waive, in its sole discretion, in whole or in part, the limitations on the
Investor's obligations to purchase shares of Common Stock contained in this
Section 2.2(a).

            (b) 4.9% Limit. Notwithstanding anything herein to the contrary, the
Investor shall not be required nor allowed to purchase, and the Company shall
not issue, shares of Common Stock pursuant to this Agreement on the Closing Date
to the extent such purchase, when aggregated with all other shares of Common
Stock then beneficially owned by the Investor, would result in the Investor or
any Affiliate of the Investor beneficially owning more than 4.9% of all the
issued and outstanding Common Stock on such Closing Date. For purposes of this
Agreement, beneficial ownership shall be calculated in accordance with Section
13(d) of the Exchange Act.

      2.3 Closings and Settlements.

            (a) Deliveries. On the Settlement Date (i) the Company shall credit
such aggregate number of shares of Common Stock that the Investor had purchased
on the Closing Date to the Investor's or its designee's balance account with The
Depository Trust Company ("DTC") through its Deposit and Withdrawal At Custodian
system or deliver such shares by such other means as may be mutually agreed upon
by the parties; and (ii) if such shares are so received no later than 1:00 p.m.
Eastern time, the Investor shall deliver to the Company's brokerage account at
the Underwriter, (or if later than 1:00 p.m. Eastern time, in funds available
the next Trading Day) on or prior to the Settlement Date, a dollar amount equal
to (A) the number of shares so received multiplied by (B) the Purchase Price. In
addition, prior to the Closing Date, each of the Company and the Investor shall
deliver all other documents, instruments and writings required to be delivered
or reasonably requested by either of them pursuant to this Agreement in order to
implement and effect the transactions contemplated herein.

            (b) Company's Failure to Deliver Shares. If the Company shall fail
to deliver shares of Common Stock to the Investor by the Settlement Date, the
Investor shall send a written notice to the Company advising the Company that
such shares have not been received. If, after such notice, the Company shall
fail to issue the shares of Common Stock by the fifth Business Day after the
Settlement Date for such shares, the Company shall pay damages to the Investor
equal to any actual damages incurred by the Investor because of the Company's
failure to deliver such required shares, including damages resulting from (A)
the Investor's need, as determined by the Investor in its sole discretion, to
"unwind" any and all sales of the Company's Common Stock made by the Investor
and to reimburse any and all purchasers for their completed purchases of the
Company's Common Stock and (B) resulting from the Investor's need to "buy in"
shares of Common Stock to the extent necessary to satisfy its securities
delivery requirements ("Buy-In Actual Damages"). Moreover, if the shares have
not been delivered by such date, the Investor will not be obligated to pay the
Company (unless the Company has already paid the Investor's actual damages, if

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any, incurred during such Selling Period) for any shares purchased by the
Investor or that the Investor agreed to purchase or was obligated to purchase
during the Selling Period. In addition, if the shares have not been delivered by
the Company by the fifth Business Day after the Settlement Date, at the
Investor's sole option, it may terminate this Agreement.

      2.4 Termination, Suspension and Modification of Investment Obligation.

            (a) Blocking Events. The Investor shall not be obligated to purchase
any shares of Common Stock from the Company when there shall exist any one or
more of the following:

                  (i) the withdrawal or suspension of the effectiveness of a
registration statement (the "Registration Statement") for the registration of
not less than the number of shares of Common Stock equal to Maximum Draw Down
Amount divided by the Hard Floor Price, which Registration Statement shall have
been declared effective by the Securities and Exchange Commission (the "SEC");

                  (ii) the failure of the Common Stock issuable hereunder to be
validly listed on the Principal Market;

                  (iii) the Company's failure to satisfy the requirements of
Section 3.1 or 3.3;

                  (iv) any failure or interruption in the compliance by the
Company with any of the covenants provided in Article VI;

                  (v) any merger or consolidation of the Company with or into,
or a transfer of all or substantially all of the assets of the Company to,
another entity; or

                  (vi) receipt or Deemed Receipt (as provided in Section 3.2) by
the Investor of a Notice of Blocking Period (each of (i), (ii), (iii), (iv), (v)
or (vi) a "Blocking Event").

            (b) The Company shall be obligated to notify the Investor in writing
using the form attached hereto as Exhibit 3.2 immediately upon the occurrence of
a Blocking Event. The Investor shall be entitled, in its sole discretion, to
waive any Blocking Event in writing.

III. CONDITIONS PRECEDENT.

      3.1 Conditions Precedent to the Obligation of the Investor to Purchase
Common Stock Pursuant to a Capital Demand Notice. The obligation of the Investor
to purchase Common Stock and to acquire and pay for Common Stock on the Closing
Date is subject to the satisfaction on the Closing Date (the "Condition
Precedent Date") of the conditions precedent set forth in Section 3.1 of the
Underwriting Agreement (other than the conditions set forth in Subsections
3.1(l) and 3.1(n)), which conditions are incorporated by reference herein as if
fully set forth in this Agreement as of the date hereof and which cannot be
waived without the prior written consent of the Investor.

      3.2 Occurrence of Material Events. If the Company's management determines
in its good faith judgment (i) that it is required or advisable to do so or (ii)
that any fact exists or any event has occurred that makes any statement of a
material fact made in the Registration Statement, the prospectus, any amendment
or supplement thereto, or any document incorporated by reference therein untrue
in any material respect, or that requires the making of any additions to or
changes in the Registration Statement or the prospectus, in order to make the
statements therein not misleading in any material respect, the Company shall
notify the Investor using the form attached hereto as Exhibit 3.2 (a "Notice of
Blocking Period") that it may not sell the Registrable Securities pursuant to
any Registration Statement or prospectus; provided, that if the Investor
reasonably believes, after advice from its attorneys and notice to after
consultation with the

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Company, that a fact exists or an event has occurred that makes any statement of
a material fact made in the Registration Statement, the prospectus, any
amendment or supplement thereto, or any document incorporated by reference
therein untrue in any material respect, or that requires the making of any
additions to or changes in the Registration Statement or the prospectus, in
order to make the statements therein not misleading in any material respect,
then the Company shall have been deemed to have delivered a Notice of Blocking
Period to the Investor ("Deemed Receipt"). The Investor agrees by acquisition of
the Registrable Securities that, upon receipt of a Notice of Blocking Period
from the Company of the existence of any fact of the kind described in the
immediately preceding sentence, the Investor shall not dispose of, sell or offer
for sale the Registrable Securities pursuant to the Registration Statement until
such Investor receives (i) copies of the supplemented or amended prospectus, or
until counsel for the Company shall have determined that such disclosure is not
required due to subsequent events, (ii) notice in writing (the "Advice") from
the Company that the use of the prospectus may be resumed and (iii) copies of
any additional or supplemental filings that are incorporated by reference in the
Prospectus. If so directed by the Company in connection with any such notice,
the Investor will deliver to the Company (at the Company's expense) all copies,
other than permanent file copies then in such Investor's possession, of the
prospectus covering such Registrable Securities that was current immediately
prior to the time of receipt of such notice.

      3.3 Due Diligence Review. The Investor shall be entitled to rely on and
have the benefits of the due diligence review conducted by the Underwriter
pursuant to Section 3.2 of the Underwriting Agreement.

IV. REPRESENTATIONS AND WARRANTIES OF INVESTOR.

            The Investor represents and warrants to the Company as follows:

      4.1 Authorization; Enforcement. The Investor has full power and authority
to execute and deliver this Agreement, and to consummate the transactions
contemplated hereby in accordance with the terms hereof. The execution and
delivery of this Agreement and the consummation of the transactions contemplated
hereby have been duly authorized by the Investor. No other proceedings on the
part of Investor are necessary to approve and authorize the execution and
delivery of this Agreement and the consummation of the transactions contemplated
hereby in accordance with the terms hereof. This Agreement has been validly
executed and delivered by the Investor and is a valid and binding agreement of
the Investor enforceable against it in accordance with its terms, subject as to
enforceability to general principles of equity and to applicable bankruptcy,
insolvency, reorganization, moratorium, liquidation and similar laws relating
to, or affecting generally the enforcement of, applicable creditors' rights and
remedies.

      4.2 Not an Affiliate. The Investor is not an officer, director or
Affiliate of the Company.

      4.3 Organization and Standing. The Investor is duly organized, validly
existing, and in good standing under the laws of Delaware, and has all requisite
power and authority to carry on its business as now being conducted, and is duly
qualified to do business and in good standing in each jurisdiction in which the
nature of the business conducted by it makes such qualifications necessary,
except where the failure to be so qualified or in good standing would not have a
material adverse effect.

      4.4 Absence of Conflicts. The execution and delivery of this Agreement and
any other document or instrument executed in connection herewith, and the
consummation of the transactions contemplated hereby and thereby, and compliance
with the requirements hereof and thereof, will not violate the provision of any
indenture, instrument or agreement to which the Investor is a party or is
subject, or by which the Investor or any of its assets is bound, or conflict
with or constitute a material default

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thereunder, or result in the creation or imposition of any lien pursuant to the
terms of any such indenture, instrument or agreement, or constitute a breach of
any fiduciary duty owed by the Investor to any third party.

V. REPRESENTATIONS AND WARRANTIES OF THE COMPANY.

            The representations and warranties of the Company set forth in
Article V of the Underwriting Agreement are incorporated by reference herein as
if fully set forth in this Agreement as of the date hereof and are for the
benefit of the Investor.

VI. COVENANTS.

            In addition to the covenant set forth below, the covenants of the
Company set forth in Article VI of the Underwriting Agreement are incorporated
by reference herein as if fully set forth in this Agreement as of the date
hereof and are for the benefit of the Investor.

      6.1 Short Selling. Investor and its Affiliates shall not engage in any
short selling activities with respect to the Company's Common Stock.

VII. ASSIGNMENT, ENTIRE AGREEMENT, AMENDMENT, TERMINATION.

      7.1 Successors and Assigns. Neither this Agreement nor any rights of the
Investor or the Company hereunder may be assigned by either party to any other
Person. Notwithstanding the foregoing, the Investor's rights and obligations
under this Agreement may be assigned at any time, in whole, with the prior
written consent of the Company (which consent shall not be unreasonably
withheld) to any Affiliate of the Investor (a "Permitted Transferee"). The
rights and obligations of the Investor under this Agreement shall inure to the
benefit of, and be enforceable by and against, any such Permitted Transferee.

      7.2 Entire Agreement; Amendment. This Agreement, the Underwriting
Agreement and the other documents delivered pursuant hereto constitute the full
and entire understanding and agreement between the parties with regard to the
subjects hereof and thereof, and supercedes all other prior oral or written
agreements between the parties, their Affiliates, or persons acting on their
behalf. No party shall be liable or bound to any other party in any manner by
any warranties, representations or covenants except as specifically set forth in
this Agreement or therein. Except as expressly provided in this Agreement,
neither this Agreement nor any term hereof may be amended, waived, discharged or
terminated other than by a written instrument signed by the party against whom
enforcement of any such amendment, waiver, discharge or termination is sought.

      7.3 Publicity. Each of the Company and the Investor agrees that they will
not disclose, and will not include in any public announcement, the name of the
other without its prior consent, unless and until such disclosure is required by
law or applicable regulation, and then only to the extent of such requirement.
Except as may be required by law, each of the Company and the Investor shall
consult with the other before issuing any press release or otherwise making any
public statements with respect to this Agreement and shall not issue any such
press release or make any such public statement prior to such consultation.

      7.4 Termination.

            (a) The Company may, in its sole discretion, terminate the
Investor's obligation to purchase any Common Stock pursuant to Section 2.1;
provided, however, that such termination shall not affect the continuing

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obligations of the Company set forth in this Agreement, including the survival
of representations, warranties, covenants and indemnification rights of the
Investor.

            (b) The Investor may (in its sole and absolute discretion) terminate
this Agreement and its obligation to purchase shares of Common Stock as a result
of (i) a breach by the Company of any material representation, warranty,
covenant or other obligation in connection with this Agreement, (ii) the failure
by the Company to comply with the requirements of Section 6.2, 6.3, 6.4, 6.5 or
6.6 of the Underwriting Agreement, (iii) the Company, at any date after the date
hereof, effecting any merger or consolidation of the Company with or into, or
transferring all or substantially all of the assets of the Company to, another
entity or (iv) the Investor reasonably determining, at any time that the
adoption of, or change in, or any change in the interpretation or application
of, any law, regulation, rule, guideline or treaty (including, but not limited
to, changes of capital adequacy) makes it illegal or materially impracticable
for the Investor to fulfill its commitment pursuant to this Agreement, but in
the case of (i) or (iv) above, the Investor may terminate this Agreement only
after a 30-day period beginning when the Investor gives the Company notice of
its intentions to terminate this Agreement (but the Investor's right to
terminate its obligation to purchase any shares of Common Stock pursuant to a
Capital Demand Notice shall not be subject to any delay or contingency), in
which, in the case of (i), the Company has not cured such breach as provided
above, or, in the case of (iv), the parties negotiate in good faith a reasonable
alternative manner not illegal or impracticable for the Investor to fulfill its
commitment pursuant to this Agreement; provided, however, that such termination
shall not affect the continuing obligations of the Company as set forth in this
Agreement, including the survival of representations, warranties, covenants and
indemnification rights of the Investor. If the Company shall fail to comply with
the requirements under Section 6.2, 6.3, 6.4, 6.5 or 6.6 of the Underwriting
Agreement pursuant to clause (ii) above, the Company shall notify the Investor
within two (2) days of the time it becomes aware of the failure to comply with
any such covenants. If the Investor elects to terminate this Agreement pursuant
to clause (ii) above, it must first give the Company notice of such election and
may terminate this Agreement only after a 10-day period in which the Company has
not cured the failure to comply with any such covenants; provided, however, that
such termination shall not affect the continuing obligations of the Company as
set forth in this Agreement, including the survival of representations,
warranties, covenants and indemnification rights of the Investor. The Investor
may also, in its sole and absolute discretion, terminate this Agreement if the
Company shall fail to maintain the listing of the Common Stock on a Principal
Market, or if trading of the Common Stock on a Principal Market shall have been
suspended for a period of ten (10) consecutive Trading Days; provided, however,
that such termination shall not affect the continuing obligations of the Company
set forth in this Agreement, including the survival of representations,
warranties, covenants and indemnification rights of the Investor. The Investor
may waive, in its sole and absolute discretion, in whole or in part, any of the
termination events contained in this Section 7.4.

            (c) Upon the termination of the Underwriting Agreement pursuant to
Section 7.4 contained therein, this Agreement shall terminate; provided,
however, that such termination shall not affect the continuing obligations of
the Company set forth in this Agreement, including the survival of
representations, warranties, covenants and indemnification rights of the
Investor.

VIII. NOTICES; COSTS AND EXPENSES.

      8.1 Notices. All notices, demands, requests, consents, approvals or other
communications required or permitted to be given hereunder or which are given
with respect to this Agreement shall be in writing and shall be (i) personally
served, (ii) deposited in the mail, registered or certified, return receipt
requested, postage prepaid, (iii) delivered by reputable air courier service
with charges prepaid, (iv) transmitted by hand delivery, or (v) transmitted by
facsimile and electronic mail, addressed as set forth below, or to such other
address as such party shall have specified most recently by written notice:

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            If to the Company, to:

            Triangle Pharmaceuticals, Inc.
            4 University Place
            4611 University Drive
            Durham, North Carolina 27707
            Attention: Andrew Finkle, Esq.
            Facsimile No.: (919) 402-1192
            Telephone No.: (919) 402-1116
            E-mail: finklera@tripharm.com

            With a copy (which shall not constitute notice) to:

            Brobeck, Phleger & Harrison LLP
            1633 Broadway
            47th Floor
            New York, New York 10019
            Attention: Ellen Corenswet, Esq.
            Facsimile No.: (212) 586-7878
            E-mail: ecorenswet@brobeck.com

            If to the Investor, to:

            Ramius Capital Group, LLC
            666 Third Avenue, 26th Floor
            New York, NY 10017
            Attention: Jeffrey M. Solomon
            Facsimile No.: (212) 845-7999

            With a copy (which shall not constitute notice) to:

            Schulte Roth & Zabel LLP
            900 Third Avenue
            New York, NY 10022
            Attention: Eleazer N. Klein, Esq.
            Facsimile No.: (212) 593-5955
            E-mail: eleazer.klein@srz.com

            Any notice sent by one party to another with confirmation of
acceptance or otherwise received in writing via courier, hand delivery or
first-class mail (return receipt requested) by the Company, or, if received on
any day which is not a Trading Day or after 12:00 noon on a Trading Day, shall
be deemed to be delivered on the immediately succeeding Trading Day. Notice
shall be deemed given on the date of service or transmission if personally
served or transmitted by facsimile or electronic mail during normal business
hours of the recipient; provided, that such transmission by facsimile or
electronic mail shall have been confirmed received. Notice otherwise sent as
provided herein shall be deemed given on the third (3rd) business day following
the date mailed or on the second business day following the date of deposit for
delivery of such notice with a reputable air courier service.

      8.2 Costs and Expenses. In the event payment from the Company to the
Underwriter is not received within the thirty (30) day period set forth in
Section 8.2 of the Underwriting Agreement, Investor shall have the

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right to deduct any such amounts owed by the Company to the Investor or the
Underwriter from any amounts owed by the Investor to the Company pursuant
hereto.

IX. INDEMNIFICATION AND CONTRIBUTION.

      9.1 Indemnification.

            (a) To the fullest extent permitted by law, the Company will, and
hereby does, indemnify, hold harmless and defend the Investor, the directors,
officers, partners, employees and agents of the Investor and each Person, if
any, who controls any Investor within the meaning of the Securities Act or the
Exchange Act (each, an "Indemnified Person"), against any losses, claims,
damages, liabilities, judgments, fines, penalties, charges, costs, 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 or NASD, 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, or the omission or alleged 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 the statements
therein were made, 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 Securities Act, the Exchange 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 breach of any representation, warranty,
covenant or agreement contained in this Agreement or any document delivered in
connection with this Agreement (the matters in the foregoing clauses (i) through
(iv) being, collectively, "Violations"). The Company shall reimburse the
Investors and each such controlling person, promptly as such expenses are
incurred and are due and payable, for any 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 9.1(a): (i) shall not apply
to a Claim arising out of or based upon a Violation which occurs in reliance
upon and in conformity with information furnished in writing to the Company by
any 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; (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, and 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; and (iii) 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

                                       8

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
<PAGE>

withheld. 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 Investor.

            (b) In connection with any Registration Statement or any amendment
or supplement thereto in which the Investor is participating, the Investor
agrees to indemnify, hold harmless and defend, to the same extent and in the
same manner as is set forth in Section 9.1(a), the Company, each of its
directors, each of its officers who signs the Registration Statement, each
Person, if any, who controls the Company within the meaning of the Securities
Act or the Exchange Act (collectively and together with an Indemnified Person,
an "Indemnified Party"), against any Claim or Indemnified Damages to which any
of them may become subject, under the Securities Act, the Exchange Act or
otherwise, insofar as such Claim or Indemnified Damages (i) 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 such Investor expressly for use in
connection with any Registration Statement covering Registrable Securities or
(ii) arise out of or are based upon the sale of Common Stock by the Investor to
any third party pursuant to the Registration Statement despite the fact that the
Investor has received a Notice of Blocking Period from the Company and has not
received the Advice from the Company signaling the end of such Blocking Period;
and, subject to Section 9.1(c), such Investor will reimburse such Indemnified
Parties promptly as such expenses are incurred and are due and payable for any
legal or other expenses reasonably incurred by them in connection with
investigating or defending any such Claim; provided, however, that the indemnity
agreement contained in this Section 9.1(b) and the agreement with respect to
contribution contained in Section 9.2 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;
provided, further, however, that the Investor shall be liable under this Section
9.1(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 Investor. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 9.1(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 receipt by an Indemnified Person or Indemnified
Party under this Section 9.1 of 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 9.1,
deliver to the indemnifying party a written notice of the commencement thereof,
and the indemnifying party shall have the right (at its expense) to participate
in, and, to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume control of the defense thereof
with counsel mutually satisfactory to the indemnifying party and the Indemnified
Person or the Indemnified Party, as the case may be; provided, however, that
such indemnifying party shall diligently pursue such defense and that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses to be paid by the indemnifying party, if, in
the reasonable opinion of counsel retained by the Indemnified Person or
Indemnified Party, as the case may be, 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. The Company shall pay reasonable fees for only one
separate legal counsel for the Investor. The Indemnified Party or Indemnified
Person shall cooperate

                                       9

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
<PAGE>

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 which 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 written consent, provided,
however, that the indemnifying party shall not unreasonably withhold, delay or
condition its consent. No indemnifying party shall, without the consent of the
Indemnified Party or Indemnified Person, consent to entry of any judgment or
enter into any settlement or other compromise which 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 within a
reasonable time of the commencement of any such action shall not relieve such
indemnifying party of any liability to the Indemnified Person or Indemnified
Party under this Section 9.1, except to the extent that the indemnifying party
is prejudiced in its ability to defend such action.

            (d) The indemnification required by this Section 9.1 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.

      9.2 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 any amounts for which it would otherwise be
liable under Section 9.1 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 9.1; (ii) no seller of Registrable Securities guilty of
fraudulent misrepresentation (within the meaning of Section 10(f) of the
Securities Act) shall be entitled to contribution from any seller 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.

X. GOVERNING LAW; MISCELLANEOUS.

      10.1 Governing Law. This Agreement shall be governed by and interpreted in
accordance with the laws of the State of New York without regard to the
principles of conflict of laws.

      10.2 Counterparts. This Agreement may be executed in any number of
counterparts, all of which shall be considered one and the same agreement and
shall become effective when counterparts have been signed by each party and
delivered to the other party. In the event any signature page is delivered by
facsimile transmission, the party using such means of delivery shall cause four
(4) additional original executed signature pages to be physically delivered to
the other party within five (5) days of the execution and delivery hereof.

                                       10

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
<PAGE>

      10.3 Headings. The headings of this Agreement are for convenience of
reference and shall not form part of, or affect the interpretation of, this
Agreement.

      10.4 Severability. 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; provided that such severability shall be
ineffective if it materially changes the economic benefit of this Agreement to
any party.

      10.5 Survival. The representations, warranties, covenants and agreements
of the parties hereto shall survive the Closing hereunder. The indemnity and
contribution agreements contained in Sections 9.1 and 9.2 hereof shall survive
and remain operative and in full force and effect regardless of (i) any
termination of this Agreement, (ii) any investigation made by or on behalf of
any indemnified party or by or on behalf of the Company, and (iii) the
consummation of the sale or successive resales of the Common Stock.

      10.6 No Third Party Beneficiaries. 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, except as provided in Article IX.

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

      10.8 Construction. 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. Unless the
context of this Agreement otherwise clearly requires, references to the plural
include the singular, the singular the plural and the part the whole and "or"
has the inclusive meaning represented by the phrase "and/or". Unless the context
requires otherwise, (i) any definition of or reference to any agreement,
instrument or other document herein shall be construed as referring to such
agreement, instrument or other document as from time to time amended,
supplemented or otherwise modified (subject to any restrictions on such
amendments, supplements or modifications set forth herein), (ii) any reference
herein to any Person shall be construed to include such Person's successors and
assigns, (iii) the words "herein", "hereof" and "hereunder", and words of
similar import, shall be construed to refer to this Agreement in its entirety
and not to any particular provision hereof, and (iv) all references herein to
Articles, Sections, Exhibits and Schedules shall be construed to refer to
Articles and Sections of, and Exhibits and Schedules to, this Agreement.

      10.9 Equitable Relief. The Company recognizes that in the event that it
fails to perform, observe, or discharge any or all of its obligations under this
Agreement, any remedy at law may prove to be inadequate relief to the Investor.
The Company therefore agrees that the Investor shall be entitled to seek
temporary and permanent injunctive relief in any such case without the necessity
of proving actual damages.

      10.10 Consent to Jurisdiction. The parties hereto expressly submit
themselves to the exclusive jurisdiction of the federal courts of New York, New
York, provided, however, that in the event that the federal courts do not have
jurisdiction then the state courts of New York, New York in any action or
proceeding relating to this Agreement or any of the other documents contemplated
hereby or any of the transactions contemplated hereby or thereby. Each party
hereby irrevocably waives, to the fullest extent permitted by law, any objection
that it may now or hereafter have to the laying of venue of any such action,
suit or proceeding brought in such a court and any claim that any such action,
suit or

                                       11

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
<PAGE>

proceeding brought in such a court has been brought in an inconvenient forum.
The parties hereto hereby irrevocably waive any and all right to a trial by jury
with respect to any legal proceeding arising out of or relating to this
Agreement or the transactions contemplated hereby. The parties hereto
irrevocably and unconditionally consent to the service of process of any of the
aforementioned courts in any such action, suit or proceeding by the mailing of
copies thereof by registered or certified mail, return receipt requested,
postage prepaid, at their respective addresses set forth or provided for herein,
such service to become effective ten (10) days after such mailing. Nothing
herein shall affect the right of any party to serve process in any manner
permitted by law or to commence legal proceedings or otherwise proceed against
the other parties in any other jurisdiction.

                                       12

PROVISIONAL PATENT APPLICATION HAS BEEN FILED
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their respective authorized officers as of the date hereof.

                                              RAMIUS CAPITAL GROUP, LLC

                                        By: /s/ MORGAN B. STARK
                                            ------------------------------------
                                            Name: Morgan B. Stark
                                            Title: Principal

                                             TRIANGLE PHARMACEUTICALS, INC.

                                        By: /s/ CHRIS A. RALLIS
                                            ------------------------------------
                                            Name: Chris A. Rallis
                                            Title: President and
                                                   Chief Operating Officer

                                       13

PROVISIONAL PATENT APPLICATION HAS BEEN FILED<PAGE>

                                                                   Exhibit 4.1

RSN

THIS CERTIFICATE IS TRANSFERABLE
IN CANTON, MA OR NEW YORK, NY

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

SEE REVERSE FOR CERTAIN DEFINITIONS
CUSIP 769320 10 2

This Certifies that
is the record holder of

FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK, $.001 PAR VALUE, OF

RIVERSTONE NETWORKS, INC.

transferable on the books of the Corporation by the holder hereof in person or
by duly authorized attorney upon surrender of this certificate properly
endorsed. This certificate is not valid until countersigned by the Transfer
Agent and registered by the Registrar.

     WITNESS the facsimile seal of the Corporation and the facsimile signatures
of its duly authorized officers.

Dated:

COUNTERSIGNED AND REGISTERED:
CHASEMELLON SHAREHOLDER SERVICES, L.L.C.
TRANSFER AGENT AND REGISTRAR
BY

AUTHORIZED SIGNATURE

PRESIDENT AND CHIEF EXECUTIVE OFFICER

SECRETARY
<PAGE>

The Corporation shall furnish without charge to each stockholder who so requests
a statement of the powers, designations, preferences and relative,
participating, optional, or other special rights of each class of stock of the
Corporation or series thereof and the qualifications, limitations or
restrictions of such preferences and/or rights. Such requests shall be made to
the Corporation's Secretary at the principal office of the Corporation.

The following abbreviations, when used in the inscription on the face of this
certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

        TEN COM         --      as tenants in common
        TEN ENT         --      as tenants by the entireties
        JT TEN          --      as joint tenants with right of survivorship and
                                not as tenants in common

                UNIF GIFT MIN ACT  --  ............................... Custodian
 .............................
                                   (Cust)
(Minor)
                              under Uniform Gifts to Minors Act
 ....................................................................
                                                             (State)

                UNIF TRF MIN ACT  --  ..................... Custodian (until age
 ....................)
                                   (Cust)
                     ..................... under Uniform Transfers to Minors Act
                           (Minor)
 ....................................................................
                                                             (State)
Additional abbreviations may also be used though not in the above list.

        For Value Received,
hereby sell(s), assign(s) and transfer(s) unto

           PLEASE INSERT SOCIAL SECURITY OR OTHER
           IDENTIFYING NUMBER OF ASSIGNEE

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

Shares
of the common stock represented by the within certificate, and do hereby
irrevocably constitute and appoint
<PAGE>

Attorney
to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.
Dated

X
X
NOTICE:

THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON
THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR
ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed

By
THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN
AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE
17Ad-15.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00016-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00016-of-00352.parquet"}]]