Document:

Registration Rights Agreement

 Exhibit 4.2 
  

REGISTRATION RIGHTS AGREEMENT 
  
 among 
  
 NEKTAR THERAPEUTICS, 
  
  
 MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED 
  
 LEHMAN BROTHERS INC. 
  
 GOLDMAN, SACHS & CO. 
  
 DEUTSCHE BANK SECURITIES INC. 
  
 W.R. HAMBRECHT + CO, LLC 
  
 LEERINK SWANN &
COMPANY 
  
 SG COWEN & CO., LLC 
  
 and 
  
 SUNTRUST CAPITAL MARKETS, INC. 
  
  
 Dated as of September 28, 2005 

 Registration Rights Agreement (the “Agreement”), dated as of September 28, 2005 among
Nektar Therapeutics, a Delaware corporation (together with any successor entity, herein referred to as the “Issuer”), Merrill Lynch, Pierce, Fenner & Smith Incorporated, Lehman Brothers Inc., Goldman, Sachs & Co.,
Deutsche Bank Securities Inc., W.R. Hambrecht + Co, LLC, Leerink Swann & Company, SG Cowen & Co., LLC and SunTrust Capital Markets, Inc. (collectively, the “Initial Purchasers”). 
  
 Pursuant to the Purchase Agreement, dated September 22, 2005, between
the Issuer and the Initial Purchasers (the “Purchase Agreement”), the Initial Purchasers have agreed to purchase from the Issuer up to $275,000,000 ($315,000,000 if the Initial Purchasers exercise the over-allotment option in full) in
aggregate principal amount of 3.25% Convertible Subordinated Notes due 2012 (the “Notes”). The Notes will be convertible into fully paid, nonassessable common stock, par value $0.0001 per share, of the Issuer (the “Common Stock”)
on the terms, and subject to the conditions, set forth in the Indenture (as defined herein). To induce the Initial Purchasers to purchase the Notes, the Issuer has agreed to provide the registration rights set forth in this Agreement pursuant to
Section 3(l) of the Purchase Agreement. 
  
 The parties
hereby agree as follows: 
  
 1. Definitions. As used in
this Agreement, the following capitalized terms shall have the following meanings: 
  
 Advice: As defined in Section 4(c)(ii) hereof. 
  
 Agreement: As defined in the preamble hereto. 
  
 Blue Sky Application: As defined in Section 6(a)(i) hereof. 
  
 Broker-Dealer: Any broker or dealer registered under the Exchange Act. 
  
 Business Day: A day other than a Saturday or Sunday or any federal holiday in the United States. 
  
 Closing Date: The date of this Agreement. 
  
 Commission: Securities and Exchange Commission. 
  
 Common Stock: As defined in the preamble hereto. 
  
 Damages Payment Date: Each Interest Payment Date. 
  
 Effectiveness Period: As defined in Section 2(a)(iii) hereof.

  
 Effectiveness Target Date: As defined in
Section 2(a)(ii) hereof. 
  
 Exchange Act: Securities
Exchange Act of 1934, as amended. 
  
 Holder: A Person who
owns, beneficially or otherwise, Transfer Restricted Securities. 
  

 1 

 Indemnified Holder: As defined in Section 6(a) hereof. 
  
 Indenture: The Indenture, dated as of September 28, 2005, between
the Issuer and J.P. Morgan Trust Company, National Association, as trustee (the “Trustee”), pursuant to which the Notes are to be issued, as such Indenture is amended, modified or supplemented from time to time in accordance with the terms
thereof. 
  
 Initial Purchasers: As defined in the preamble
hereto. 
  
 Interest Payment Date: As defined in the
Indenture. 
  
 Issuer: As defined in the preamble hereto.

  
 Liquidated Damages: As defined in Section 3(a)
hereof. 
  
 Majority of Holders: Holders holding over 50%
of the aggregate principal amount of Notes outstanding; provided that, for purpose of this definition, a holder of shares of Common Stock which constitute Transfer Restricted Securities and were issued upon conversion of the Notes shall be deemed to
hold an aggregate principal amount of Notes (in addition to the aggregate principal amount of Notes held by such holder) equal to the aggregate principal amount of Notes converted by such Holder into such shares of Common Stock. 
  
 NASD: National Association of Securities Dealers, Inc. 
  
 Notes: As defined in the preamble hereto. 
  
 Person: An individual, partnership, corporation, unincorporated
organization, trust, joint venture or a government or agency or political subdivision thereof. 
  
 Prospectus: The prospectus included in a Shelf Registration Statement, as amended or supplemented by any prospectus supplement and by all other amendments thereto, including post-effective amendments, and all
material incorporated by reference into such Prospectus. 
  
 Questionnaire Deadline: As defined in Section 2(b) hereof. 
  
 Record Holder: With respect to any Damages Payment Date, each Person who is a Holder on the record date with respect to the Interest Payment Date on which such Damages Payment Date shall occur. 
  
 Registration Default: As defined in Section 3(a) hereof.

  
 Sale Notice: As defined in Section 4(e) hereof.

  
 Securities Act: Securities Act of 1933, as amended.

  
 Shelf Filing Deadline: As defined in
Section 2(a)(i) hereof. 
  
 Shelf Registration
Statement: As defined in Section 2(a)(i) hereof. 
  

 2 

 Suspension Period. As defined in Section 4(b)(i) hereof. 
  
 TIA: Trust Indenture Act of 1939, as in effect on the date the
Indenture is qualified under the TIA. 
  
 Transfer Restricted
Securities: Each Note and each share of Common Stock issued upon conversion of Notes until the earlier of: 
  
 (i) the date on which such Note or such share of Common Stock issued upon conversion has been effectively registered under the Securities
Act and disposed of in accordance with the Shelf Registration Statement; 
  
 (ii) the date on which such Note or such share of Common Stock issued upon conversion is transferred in compliance with Rule 144 under the Securities Act or may be sold or transferred pursuant to Rule 144 under the
Securities Act (or any other similar provision then in force); or 
  
 (iii) the date on which such Note or such share of Common Stock issued upon conversion ceases to be outstanding (whether as a result of redemption, repurchase and cancellation, conversion or otherwise). 
  
 Underwritten Registration or Underwritten Offering: A registration in
which securities of the Issuer are sold to an underwriter for reoffering to the public. 
  
 2. Shelf Registration. 
  
 (a) The Issuer shall: 
  
 (i) not later
than 90 days after the date hereof (the “Shelf Filing Deadline”), cause to be filed a registration statement pursuant to Rule 415 under the Securities Act (the “Shelf Registration Statement”), which Shelf Registration Statement
shall provide for resales of all Transfer Restricted Securities held by Holders that have provided the information required pursuant to the terms of Section 2(b) hereof; 
  
 (ii) use its best efforts to cause the Shelf Registration Statement to be declared effective by the
Commission as promptly as reasonably practicable, but in no event later than 210 days after the date hereof (the “Effectiveness Target Date”); and 
  
 (iii) use its best efforts to keep the Shelf Registration Statement continuously effective, supplemented and amended as required by the
provisions of Section 4(b) hereof to the extent necessary to ensure that (A) it is available for resales by the Holders of Transfer Restricted Securities entitled to the benefit of this Agreement and (B) conforms with the requirements
of this Agreement and the Securities Act and the rules and regulations of the Commission promulgated thereunder as announced from time to time for a period (the “Effectiveness Period”) of: 
  
 (A) two years following the last date of original issuance
of Notes; or 
  

 3 

 (B) such shorter period that will terminate when (x) all of the Holders of Transfer
Restricted Securities are able to sell all Transfer Restricted Securities immediately without restriction pursuant to Rule 144(k) under the Securities Act or any successor rule thereto, (y) when all Transfer Restricted Securities have ceased to
be outstanding (whether as a result of redemption, repurchase and cancellation, conversion or otherwise) or (z) all Transfer Restricted Securities registered under the Shelf Registration Statement have been sold. 
  
 (b) No Holder of Transfer Restricted Securities may include any of its
Transfer Restricted Securities in the Shelf Registration Statement pursuant to this Agreement unless such Holder furnishes to the Issuer in writing, prior to or on the 20th Business Day after receipt of a request therefor (the “Questionnaire
Deadline”), such information as the Issuer may reasonably request for use in connection with the Shelf Registration Statement or the Prospectus or preliminary Prospectus included therein and in any application to be filed with or under state
securities laws. In connection with all such requests for information from Holders of Transfer Restricted Securities, the Issuer shall notify such Holders of the requirements set forth in the preceding sentence. No Holder of Transfer Restricted
Securities shall be entitled to Liquidated Damages pursuant to Section 3 hereof unless such Holder shall have provided all such reasonably requested information prior to or on the Questionnaire Deadline. Each Holder as to which the Shelf
Registration Statement is being effected agrees to furnish promptly to the Issuer all information required to be disclosed in order to make information previously furnished to the Issuer by such Holder not materially misleading. 
  
 3. Liquidated Damages. 
  
 (a) If: 
  
 (i) the Shelf Registration Statement is not filed with the Commission prior to or on the Shelf Filing
Deadline; 
  
 (ii) the Shelf Registration
Statement has not been declared effective by the Commission prior to or on the Effectiveness Target Date; 
  
 (iii) subject to the provisions of Section 4(b)(i) hereof, the Shelf Registration Statement is filed and declared effective but,
during the Effectiveness Period, shall thereafter cease to be effective or fail to be usable for its intended purpose without being succeeded within five Business Days by a post-effective amendment to the Shelf Registration Statement or a report
filed with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act that cures such failure and, in the case of a post-effective amendment, is itself immediately declared effective; or 
  
 (iv) prior to or on the 45th, 60th or 90th day, as the case may be, of any Suspension Period, such suspension has not been terminated,

  
 (each such event referred to in foregoing clauses
(i) through (iv), a “Registration Default”), the Issuer hereby agrees to pay additional interest as liquidated damages (“Liquidated Damages”) with respect to Notes that constitute Transfer Restricted Securities, from and
including the day following the Registration Default to but 
  

 4 

 excluding the day on which the Registration Default has been cured, to each holder of such Notes,
(x) with respect to the first 90-day period during which a Registration Default shall have occurred and be continuing, in an amount per year equal to an additional 0.25% of the principal amount of the Notes, and (y) with respect to the
period commencing on the 91st day following the day the Registration Default shall have occurred and be continuing, in an amount per year equal to an additional 0.50% of the principal amount of the Notes; provided that in no event shall Liquidated
Damages accrue at a rate per year exceeding 0.50% of the principal amount of the Notes. 
  
 (b) All accrued Liquidated Damages shall be paid in arrears to Record Holders by the Issuer on each Damages Payment Date by wire transfer of immediately available funds or by federal funds check. Following the cure of
all Registration Defaults relating to any particular Note, the accrual of Liquidated Damages with respect to such Note will cease. 
  
 (c) In no event will Liquidated Damages be payable in respect of shares of Common Stock received by a holder of Notes upon conversion of such Notes.

  
 All obligations of the Issuer set forth in this Section 3
that are outstanding with respect to any Transfer Restricted Security 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 Transfer Restricted Security shall
have been satisfied in full. 
  
 The Liquidated Damages set forth
above shall be the exclusive monetary remedy available to the Holders of Transfer Restricted Securities for such Registration Default. 
  
 4. Registration Procedures. 
  
 (a) In connection with the Shelf Registration Statement, the Issuer shall comply with all the provisions of Section 4(b) hereof and shall use its
best efforts to effect such registration to permit the sale of the Transfer Restricted Securities being sold in accordance with the intended method or methods of distribution thereof, and pursuant thereto, shall as expeditiously as possible prepare
and file with the Commission a Shelf Registration Statement relating to the registration on any appropriate form under the Securities Act. 
  
 (b) In connection with the Shelf Registration Statement and any Prospectus required by this Agreement to permit the sale or resale of Transfer Restricted
Securities, the Issuer shall: 
  
 (i) Subject to
any notice by the Issuer in accordance with this Section 4(b) of the existence of any fact or event of the kind described in Section 4(b)(iii)(D), use its best efforts to keep the Shelf Registration Statement continuously effective during
the Effectiveness Period; upon the occurrence of any event that would cause the Shelf Registration Statement or the Prospectus contained therein (A) to contain a material misstatement or omission or (B) not be effective and usable for
resale of Transfer Restricted Securities during the Effectiveness Period, the Issuer shall file promptly an appropriate amendment to the Shelf Registration Statement or a report filed with the Commission pursuant to Section 13(a), 13(c), 14 or
15(d) of the Exchange Act, in the case of clause (A), correcting any such misstatement or omission, and, in the case of either clause (A) or (B), use its best efforts to cause such amendment to be declared 
  

 5 

 effective and the Shelf Registration Statement and the related Prospectus to become usable for their
intended purposes as soon as practicable thereafter. Notwithstanding the foregoing, the Issuer may suspend the effectiveness of the Shelf Registration Statement by written notice to the Holders for a period not to exceed an aggregate of 45 days in
any 90-day period (each such period, a “Suspension Period”) if: 
  
 (x) an event occurs and is continuing as a result of which the Shelf Registration Statement would, in the Issuer’s reasonable judgment, 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 not misleading; and 
  
 (y) the Issuer reasonably determines that the disclosure of such event at such time would have a material adverse effect on the business
of the Issuer (and its subsidiaries, if any, taken as a whole); 
  
 provided
that in the event the disclosure relates to a previously undisclosed proposed or pending material business transaction, the disclosure of which would impede the Issuer’s ability to consummate such transaction, the Issuer may extend a
Suspension Period from 45 days to 60 days; provided, however, that Suspension Periods shall not exceed an aggregate of 90 days in any 360-day period. 
  
 (ii) After the Shelf Registration Statement has been declared effective, prepare and file with the Commission (x) if permitted by the
Commission to file a prospectus supplement, within 15 Business Days’ receipt of a completed questionnaire, file such supplement to the related prospectus or (y) within 30 days of receipt of a completed questionnaire, such amendments and
post-effective amendments to the Shelf Registration Statement as may be necessary to keep the Shelf Registration Statement effective during the Effectiveness Period; cause the Prospectus to be supplemented by any required Prospectus supplement, and
as so supplemented to be filed pursuant to Rule 424 under the Securities Act, and to comply fully with the applicable provisions of Rules 424 and 430A under the Securities Act in a timely manner; and comply with the provisions of the Securities Act
with respect to the disposition of all securities covered by the Shelf Registration Statement during the applicable period in accordance with the intended method or methods of distribution by the sellers thereof set forth in the Shelf Registration
Statement or supplement to the Prospectus. Notwithstanding the foregoing, the Issuer shall not be required to file any post-effective amendments to the Shelf Registration Statement until such time as the Issuer has received questionnaires from
Holders of at least $10 million aggregate principal amount of Notes. In no event shall the Issuer be required to file more than one post-effective amendment per fiscal quarter. 
  
 (iii) Advise the underwriter(s), if any, and selling Holders promptly (but in any event within five Business
Days) and, if requested by such Persons, to confirm such advice in writing: 
  
 (A) when the Prospectus or any Prospectus supplement or post-effective amendment has been filed, and, with respect to the Shelf Registration Statement or any post-effective amendment thereto, when the same has become
effective, 
  

 6 

 (B) of any request by the Commission for amendments to the Shelf Registration Statement
or amendments or supplements to the Prospectus or for additional information relating thereto, 
  
 (C) of the issuance by the Commission of any stop order suspending the effectiveness of the Shelf Registration Statement under the
Securities Act or of the suspension by any state securities commission of the qualification of the Transfer Restricted Securities for offering or sale in any jurisdiction, or the initiation of any proceeding for any of the preceding purposes, or

  
 (D) of the existence of any fact or the
happening of any event, during the Effectiveness Period, that makes any statement of a material fact made in the Shelf Registration Statement, the Prospectus, any amendment or supplement thereto, or any document incorporated by reference therein
untrue, or that requires the making of any additions to or changes in the Shelf Registration Statement or the Prospectus in order to make the statements therein not misleading. 
  
 If at any time the Commission shall issue any stop order suspending the effectiveness of the Shelf Registration Statement, or any state
securities commission or other regulatory authority shall issue an order suspending the qualification or exemption from qualification of the Transfer Restricted Securities under state securities or Blue Sky laws, the Issuer shall use its reasonable
best efforts to obtain the withdrawal or lifting of such order at the earliest possible time. 
  
 (iv) Furnish to counsel for the Initial Purchasers, before filing with the Commission, a copy of the Shelf Registration Statement and
copies of any Prospectus included therein or any amendments or supplements to the Shelf Registration Statement or Prospectus (other than documents incorporated by reference after the initial filing of the Shelf Registration Statement), which
documents will be subject to the review of such counsel, for a period of at least five Business Days, and the Issuer will not file any Shelf Registration Statement or Prospectus or any amendment or supplement to the Shelf Registration Statement or
Prospectus (other than documents incorporated by reference) to which such counsel shall reasonably object within five Business Days after the receipt thereof. Counsel for the Initial Purchasers shall be deemed to have reasonably objected to such
filing if the Shelf Registration Statement, amendment, Prospectus or supplement, as applicable, as proposed to be filed, contains a material misstatement or omission. Notwithstanding the foregoing, the Issuer shall not be required to furnish counsel
for the Initial Purchasers with any amendment or supplement to the Shelf Registration Statement or Prospectus filed solely to reflect changes to the amount of Notes held by any particular Holder at the request of such Holder or immaterial revisions
to the information contained therein. 
  
 (v)
Make available at reasonable times for inspection by one or more representatives of the selling Holders, designated in writing by a Majority of Holders whose Transfer Restricted Securities are included in the Shelf Registration Statement,

  

 7 

 any underwriter participating in any distribution pursuant to the Shelf Registration Statement, and any
attorney or accountant retained by such selling Holders or any of the underwriter(s), all financial and other records, pertinent corporate documents and properties of the Issuer as shall be reasonably necessary to enable them to exercise any
applicable due diligence responsibilities, and cause the Issuer’s officers, directors, managers and employees to supply all information reasonably requested by any such representative or representatives of the selling Holders, underwriter,
attorney or accountant in connection with the Shelf Registration Statement after the filing thereof and before its effectiveness; provided, however, that any information designated by the Company as confidential at the time of delivery of such
information shall be kept confidential by the recipient thereof. 
  
 (vi) If requested by any selling Holders or the underwriter(s), if any, promptly incorporate in the Shelf Registration Statement or Prospectus, pursuant to a supplement or post-effective amendment if necessary, such
information as such selling Holders and underwriter(s), if any, may reasonably request to have included therein, including, without limitation: (1) information relating to the “Plan of Distribution” of the Transfer Restricted
Securities, (2) information with respect to the principal amount of Notes or number of shares of Common Stock being sold to such underwriter(s), (3) the purchase price being paid therefor and (4) any other terms of the offering of the
Transfer Restricted Securities to be sold in such offering; and make all required filings of such Prospectus supplement or post-effective amendment as soon as reasonably practicable after the Issuer is notified of the matters to be incorporated in
such Prospectus supplement or post-effective amendment. Notwithstanding the foregoing, following the effective date of the Shelf Registration Statement, the Issuer shall not be required to file more than one such supplement to reflect changes in the
amount of Notes held by any particular Holder at the request of such Holder in any 15-day period and in no event shall the Issuer be required to file more than one such post-effective amendment in any fiscal quarter. 
  
 (vii) Furnish to each selling Holder and each of the
underwriter(s), if any, without charge, at least one copy of the Shelf Registration Statement, as first filed with the Commission, and of each amendment thereto (and any documents incorporated by reference therein or exhibits thereto (or exhibits
incorporated in such exhibits by reference) as such Person may request). 
  
 (viii) Deliver to each selling Holder and each of the underwriter(s), if any, without charge, as many copies of the Prospectus (including each preliminary prospectus) and any amendment or supplement thereto as such
Persons reasonably may request; subject to any notice by the Issuer in accordance with this Section 4(b) of the existence of any fact or event of the kind described in Section 4(b)(iii)(D), the Issuer hereby consents to the use of the
Prospectus and any amendment or supplement thereto by each of the selling Holders and each of the underwriter(s), if any, in connection with the offering and the sale of the Transfer Restricted Securities covered by the Prospectus or any amendment
or supplement thereto. 
  

 8 

 (ix) If an underwriting agreement is entered into and the registration is an Underwritten
Registration, the Issuer shall: 
  
 (A) upon
request, furnish to each selling Holder and each underwriter, in such substance and scope as they may reasonably request and as are customarily made by issuers to underwriters in primary underwritten offerings, upon the date of closing of any sale
of Transfer Restricted Securities in an Underwritten Registration: 
  
 (1) a certificate, dated the date of such closing, signed by the Chief Financial Officer of the Issuer confirming, as of the date thereof, the matters set forth in Section 5(g) of the Purchase Agreement and such
other matters as such parties may reasonably request; 
  
 (2) opinions, each dated the date of such closing, of counsel to the Issuer covering such of the matters set forth in Sections 5(c) and 5(d) of the Purchase Agreement as are customarily covered in legal opinions to underwriters in
connection with primary underwritten offerings of securities; and 
  
 (3) customary comfort letters, dated the date of such closing, from the Issuer’s independent registered public accounting firm (and from any other independent registered public accounting firm whose report is
contained or incorporated by reference in the Shelf Registration Statement), in the customary form and covering matters of the type customarily covered in comfort letters to underwriters in connection with primary underwritten offerings of
securities; 
  
 (B) set forth in full in the
underwriting agreement, if any, indemnification provisions and procedures which provide rights no less protective than those set forth in Section 6 hereof with respect to all parties to be indemnified; and 
  
 (C) deliver such other documents and certificates as may be
reasonably requested by such parties to evidence compliance with clause (A) above and with any customary conditions contained in the underwriting agreement or other agreement entered into by the selling Holders pursuant to this clause (ix).

  
 (D) if requested by any underwriters, make
appropriate officers of the Issuer available to such underwriters for meetings with prospective purchasers of the Transfer Restricted Securities and prepare and present to potential investors customary “road show” materials in a manner
consistent with new issuances of securities similar to the Transfer Restricted Securities. 
  
 (x) Before any public offering of Transfer Restricted Securities, cooperate with the selling Holders, the underwriter(s), if any, and
their respective counsel in connection with the registration and qualification of the Transfer Restricted Securities under the securities or Blue Sky laws of such jurisdictions as the selling Holders or underwriter(s), if any, may reasonably request
and do any and all other acts or things necessary or advisable to enable the disposition in such jurisdictions of the Transfer 
  

 9 

 Restricted Securities covered by the Shelf Registration Statement; provided, however, that the Issuer
shall not be required (A) to register or qualify as a foreign corporation or a dealer of securities where it is not now so qualified or to take any action that would subject it to the service of process in any jurisdiction where it is not now
so subject or (B) to subject themselves to taxation in any such jurisdiction if they are not now so subject. 
  
 (xi) Cooperate with the selling Holders and the underwriter(s), if any, to facilitate the timely preparation and delivery of certificates
representing Transfer Restricted Securities to be sold and not bearing any restrictive legends (unless required by applicable securities laws); and enable such Transfer Restricted Securities to be in such denominations and registered in such names
as the Holders or the underwriter(s), if any, may request at least two Business Days before any sale of Transfer Restricted Securities made by such underwriter(s). 
  
 (xii) Use its best efforts to cause the Transfer Restricted Securities covered by the Shelf Registration
Statement to be registered with or approved by such other U.S. governmental agencies or authorities as may be necessary to enable the seller or sellers thereof or the underwriter(s), if any, to consummate the disposition of such Transfer Restricted
Securities. 
  
 (xiii) Subject to
Section 4(b)(i) hereof, if any fact or event contemplated by Section 4(b)(iii)(D) hereof shall exist or have occurred, use its reasonable best efforts to prepare a supplement or post-effective amendment to the Shelf Registration Statement
or related Prospectus or any document incorporated therein by reference or file any other required document so that, as thereafter delivered to the purchasers of Transfer Restricted Securities, the Prospectus will not contain an 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. 
  
 (xiv) Provide CUSIP numbers for all Transfer Restricted Securities not later than the effective date of the Shelf Registration Statement
and provide the Trustee under the Indenture with certificates for the Notes that are in a form eligible for deposit with The Depository Trust Company. 
  
 (xv) Cooperate and assist in any filings required to be made with the NASD and in the performance of any due diligence investigation by
any underwriter that is required to be retained in accordance with the rules and regulations of the NASD. 
  
 (xvi) Otherwise use its best efforts to comply with all applicable rules and regulations of the Commission and all reporting requirements
under the rules and regulations of the Exchange Act. 
  
 (xvii) Cause the Indenture to be qualified under the TIA not later than the effective date of the Shelf Registration Statement required by this Agreement, and, in connection therewith, cooperate with the trustee and the holders of Notes to
effect such changes to the Indenture 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 
  

 10 

 trustee thereunder to execute all documents that may be required to effect such changes and all other
forms and documents required to be filed with the Commission to enable such Indenture to be so qualified in a timely manner. 
  
 (xviii) Cause all Transfer Restricted Securities covered by the Shelf Registration Statement to be listed or quoted, as the case may be,
on each securities exchange or automated quotation system on which similar securities issued by the Issuer are then listed or quoted. 
  
 (xix) Provide promptly to each Holder upon written request each document filed with the Commission pursuant to the requirements of
Section 13 and Section 15 of the Exchange Act after the effective date of the Shelf Registration Statement. 
  
 (c) Each Holder agrees by acquisition of a Transfer Restricted Security that, upon receipt of any notice from the Issuer of the existence of any fact of
the kind described in Section 4(b)(iii)(D) hereof, such Holder will, and will use its reasonable best efforts to cause any underwriter(s) in an Underwritten Offering to, forthwith discontinue disposition of Transfer Restricted Securities
pursuant to the Shelf Registration Statement until: 
  
 (i) such Holder has received copies of the supplemented or amended Prospectus contemplated by Section 4(b)(xiii) hereof; or 
  
 (ii) such Holder is advised in writing (the “Advice”) by the Issuer that the use of the Prospectus may be resumed, and has
received copies of any additional or supplemental filings that are incorporated by reference in the Prospectus. 
  
 If so directed by the Issuer, each Holder will deliver to the Issuer (at the Issuer’s expense) all copies, other than permanent file copies then in such
Holder’s possession, of the Prospectus covering such Transfer Restricted Securities that was current at the time of receipt of such notice of suspension. 
  

(d) Each Holder who intends to be named as a selling Holder in the Shelf Registration Statement shall furnish to the Issuer in writing, within 20
Business Days after receipt of a request therefor as set forth in a questionnaire, such information regarding such Holder and the proposed distribution by such Holder of its Transfer Restricted Securities as the Issuer may reasonably request for use
in connection with the Shelf Registration Statement or Prospectus or preliminary Prospectus included therein. (The form of the questionnaire is attached hereto as Exhibit A.) Holders that do not complete the questionnaire and deliver it to the
Issuer shall not be named as selling securityholders in the Prospectus or preliminary Prospectus included in the Shelf Registration Statement and therefore shall not be permitted to sell any Transfer Restricted Securities pursuant to the Shelf
Registration Statement. Each Holder who intends to be named as a selling Holder in the Shelf Registration Statement shall promptly furnish to the Issuer in writing such other information as the Issuer may from time to time reasonably request in
writing. 
  
 (e) Upon the effectiveness of the Shelf Registration
Statement, each Holder shall notify the Issuer at least three Business Days prior to any intended distribution of Transfer Restricted Securities pursuant to the Shelf Registration Statement (a “Sale Notice”), which notice shall be
effective for five Business Days. Each Holder of a Transfer Restricted Security, by 
  

 11 

 accepting the same, agrees to hold any communication by the Company in response to a Sale Notice in confidence. Upon any
transfer of Transfer Restricted Securities pursuant to the Shelf Registration Statement, each Holder shall comply with all such Holder’s obligations relating to delivery of the Prospectus under applicable securities laws. The Issuer and its
representatives shall be entitled to rely on the foregoing covenant as evidence of compliance with such obligations by such Holder in connection with (i) any instruction requested of it in connection with such transfer by the Trustee of the
Notes or the transfer agent of the Common Stock or (ii) any representation made by the Issuer or such representative to any governing authority, including, the Commission or NASD. 
  
 5. Registration Expenses. 
  

(a) All expenses incident to the Issuer’s performance of or compliance with this Agreement shall be borne by the Issuer regardless of whether a
Shelf Registration Statement becomes effective, including, without limitation: 
  
 (i) all registration and filing fees and expenses (including filings made by any Initial Purchasers or Holders with the NASD); 

 
 (ii) all fees and expenses of compliance with federal
securities and state Blue Sky or securities laws; 
  
 (iii) all expenses of printing (including printing of Prospectuses and certificates for the Common Stock to be issued upon conversion of the Notes), messenger and delivery services and telephone charges; 
  
 (iv) all fees and disbursements of counsel to the Issuer
and, subject to Section 5(b) below, the Holders of Transfer Restricted Securities; 
  
 (v) all application and filing fees in connection with listing (or authorizing for quotation) the Common Stock on a national securities
exchange or automated quotation system pursuant to the requirements hereof; and 
  
 (vi) all fees and disbursements of the independent registered public accounting firm of the Issuer (including the expenses of any special
audit and comfort letters required by or incident to such performance). 
  
 The Issuer shall bear its internal expenses (including, without limitation, all salaries and expenses of their officers and employees performing legal, accounting or other duties), the expenses of any annual audit and the fees and expenses
of any Person, including special experts, retained by the Issuer. 
  
 (b) In connection with the Shelf Registration Statement required by this Agreement, the Issuer shall reimburse the Initial Purchasers and the Holders of Transfer Restricted Securities being registered pursuant to the Shelf Registration
Statement, as applicable, for the reasonable fees and disbursements of not more than one counsel, which shall be Sidley Austin Brown & Wood LLP, or such other counsel as may be chosen by a Majority of Holders for whose
benefit the Shelf Registration Statement is being prepared. 
  

 12 

 6. Indemnification and Contribution. 
  
 (a) The Issuer shall indemnify and hold harmless each Holder, such
Holder’s officers and employees and each person, if any, who controls such Holder within the meaning of the Securities Act (each, an “Indemnified Holder”), from and against any loss, claim, damage or liability, joint or several, or
any action in respect thereof (including, but not limited to, any loss, claim, damage, liability or action relating to resales of the Transfer Restricted Securities), to which such Indemnified Holder may become subject, insofar as any such loss,
claim, damage, liability or action arises out of, or is based upon: 
  
 (i) any untrue statement or alleged untrue statement of a material fact contained in (A) the Shelf Registration Statement or Prospectus or any amendment or supplement thereto or (B) any blue sky application
or other document or any amendment or supplement thereto prepared or executed by the Issuer (or based upon written information furnished by or on behalf of the Issuer expressly for use in such blue sky application or other document or amendment on
supplement) filed in any jurisdiction specifically for the purpose of qualifying any or all of the Transfer Restricted Securities under the securities law of any state or other jurisdiction (such application or document being hereinafter called a
“Blue Sky Application”); or 
  
 (ii)
the omission or alleged omission to state therein any material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, 
  
 and shall reimburse each Indemnified Holder promptly upon demand for any legal or other
expenses reasonably incurred by such Indemnified Holder in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred; provided, however, that the Issuer
shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of, or is based upon, any untrue statement or alleged untrue statement or omission or alleged omission made in the Shelf
Registration Statement or Prospectus or amendment or supplement thereto or Blue Sky Application in reliance upon and in conformity with written information furnished to the Issuer by or on behalf of any Holder (or its related Indemnified Holder)
specifically for use therein. The foregoing indemnity agreement is in addition to any liability which the Issuer may otherwise have to any Indemnified Holder. 
  

(b) Each Holder, severally and not jointly, shall indemnify and hold harmless the Issuer, its officers and employees and each person, if any, who
controls the Issuer within the meaning of the Securities Act, from and against any loss, claim, damage or liability, joint or several, or any action in respect thereof, to which the Issuer or any such officer, employee or controlling person may
become subject, insofar as any such loss, claim, damage or liability or action arises out of, or is based upon: 
  
 (i) any untrue statement or alleged untrue statement of any material fact contained in the Shelf Registration Statement or Prospectus or
any amendment or supplement thereto or any Blue Sky Application; or 
  

 13 

 (ii) the omission or the alleged omission to state therein 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, 
  
 but in each case only to the extent that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity
with written information furnished to the Issuer by or on behalf of such Holder (or its related Indemnified Holder) specifically for use therein, and shall reimburse the Issuer and any such officer, employee or controlling person promptly upon
demand for any legal or other expenses reasonably incurred by the Issuer or any such officer, employee or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or
action as such expenses are incurred. The foregoing indemnity agreement is in addition to any liability which any Holder may otherwise have to the Issuer and any such officer, employee or controlling person. 
  
 (c) Promptly after receipt by an indemnified party under this Section 6
of notice of any claim or the commencement of any action, the indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under this Section 6, notify the indemnifying party in writing of the claim or the
commencement of that action; provided, however, that the failure to notify the indemnifying party shall not relieve it from any liability which it may have under this Section 6 except to the extent it has been materially prejudiced by such
failure and, provided, further, that the failure to notify the indemnifying party shall not relieve it from any liability which it may have to an indemnified party otherwise than under this Section 6. If any such claim or action shall be
brought against an indemnified party, and it shall notify the indemnifying party thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it wishes, jointly with any other similarly notified indemnifying
party, to assume the defense thereof with counsel satisfactory to the indemnified party. After notice from the indemnifying party to the indemnified party of its election to assume the defense of such claim or action, the indemnifying party shall
not be liable to the indemnified party under this Section 6 for any legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however,
that a Majority of Holders shall have the right to employ a single counsel to represent jointly a Majority of Holders and their respective officers, employees and controlling persons who may be subject to liability arising out of any claim in
respect of which indemnity may be sought by a Majority of Holders against the Issuer under this Section 6, if a Majority of Holders shall have reasonably concluded that there may be one or more legal defenses available to them and their
respective officers, employees and controlling persons that are different from or additional to those available to the Issuer and its officers, employees and controlling persons, the fees and expenses of a single separate counsel shall be paid by
the Issuer. No indemnifying party shall: 
  
 (i)
without the prior written consent of the indemnified parties (which consent shall not be unreasonably withheld) settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding
in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent (1) includes an
unconditional release of each 
  

 14 

 indemnified party from all liability arising out of such claim, action, suit or proceeding and
(2) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party, or 
  
 (ii) be liable for any settlement of any such action effected without its written consent (which consent shall not be unreasonably
withheld), but if settled with its written consent or if there be a final judgment for the plaintiff in any such action, the indemnifying party agrees to indemnify and hold harmless any indemnified party from and against any loss of liability by
reason of such settlement or judgment. 
  
 (d) If the
indemnification provided for in this Section 6 shall for any reason be unavailable or insufficient to hold harmless an indemnified party under Section 6(a) or 6(b) in respect of any loss, claim, damage or liability (or action in respect
thereof) referred to therein, each indemnifying party shall, in lieu of indemnifying such indemnified party, contribute to the amount paid or payable by such indemnified party as a result of such loss, claim, damage or liability (or action in
respect thereof): 
  
 (i) in such proportion as
is appropriate to reflect the relative benefits received by the Issuer from the offering and sale of the Transfer Restricted Securities on the one hand and a Holder with respect to the sale by such Holder of the Transfer Restricted Securities on the
other, or 
  
 (ii) if the allocation provided by
clause (6)(d)(i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause 6(d)(i) but also the relative fault of the Issuer on the one hand and the Holders on the
other in connection with the statements or omissions or alleged statements or alleged omissions that resulted in such loss, claim, damage or liability (or action in respect thereof), as well as any other relevant equitable considerations.

  
 The relative benefits received by the Issuer on the one hand
and a Holder on the other with respect to such offering and such sale shall be deemed to be in the same proportion as the total net proceeds from the offering of the Notes purchased under the Purchase Agreement (before deducting expenses) received
by the Issuer as set forth in the table appearing in the section entitled “Plan of Distribution” in the Offering Memorandum, dated September 22, 2005, on the one hand, bear to the total proceeds received by such Holder with respect to
its sale if Transfer Restricted Securities on the other. 
  
 The
relative fault of the parties shall be determined by reference to whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Issuer on the one
hand or the Holders on the other, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such statement or omission. 
  
 The Issuer and each Holder agree that it would not be just and equitable if the amount of contribution pursuant to this
Section 6(d) were determined by pro rata allocation or by any other method of allocation that does not take into account the equitable considerations referred to in the first sentence of this paragraph (d). The amount paid or payable by an
indemnified party as a 
  

 15 

 result of the loss, claim, damage or liability, or action in respect thereof, referred to above in this Section 6
shall be deemed to include, for purposes of this Section 6, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating, or defending or preparing to defend any such litigation, investigation or
proceeding by any governmental agency or body, or commenced or threatened action or claim. Notwithstanding the provisions of this Section 6, no Holder shall be required to contribute any amount in excess of the amount by which the total price
at which the Transfer Restricted Securities purchased by it were resold exceeds the amount of any damages which such Holder has otherwise been required to pay by reason of any 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 Holders’ obligations to contribute as provided in this Section 6(d) are
several and not joint. 
  
 7. Rule 144A. In the event the
Issuer is not subject to Section 13 or 15(d) of the Exchange Act, the Issuer hereby agrees with each Holder, for so long as any Transfer Restricted Securities remain outstanding, to make available to any Holder or beneficial owner of Transfer
Restricted Securities in connection with any sale thereof and any prospective purchaser of such Transfer Restricted Securities from such Holder or beneficial owner, the information required by Rule 144A(d)(4) under the Securities Act in order to
permit resales of such Transfer Restricted Securities pursuant to Rule 144A. 
  
 8. Participation in Underwritten Registrations. No Holder may participate in any Underwritten Registration hereunder unless such Holder: 
  
 (i) agrees to sell such Holder’s Transfer Restricted Securities on the basis provided in any
underwriting arrangements approved by the Persons entitled hereunder to approve such arrangements and 
  
 (ii) completes and executes all reasonable questionnaires, powers of attorney, indemnities, underwriting agreements, lock-up letters and
other documents required under the terms of such underwriting arrangements. 
  
 9. Selection of Underwriters. The Holders of Transfer Restricted Securities covered by the Shelf Registration Statement who desire to do so may sell such Transfer Restricted Securities in an Underwritten
Offering. In any such Underwritten Offering, the investment banker or investment bankers and manager or managers that will administer the offering will be selected by a Majority of Holders whose Transfer Restricted Securities are included in such
offering; provided, that such investment bankers and managers must be reasonably satisfactory to the Issuer. 
  
 10. Miscellaneous. 
  
 (a) Remedies. The Issuer acknowledges and agrees that any failure by the Issuer to comply with its obligations under Section 2 hereof may
result in material irreparable injury to the Initial Purchasers or the Holders for which there is no adequate remedy at law, that it will not be possible to measure damages for such injuries precisely and that, in the event of any such failure,

  

 16 

 the Initial Purchasers or any Holder may obtain such relief as may be required to specifically enforce the Issuer’s
obligations under Section 2 hereof. The Issuer further agrees to waive the defense in any action for specific performance that a remedy at law would be adequate. 
  
 (b) Adjustments Affecting Transfer Restricted Securities. The Issuer shall not, directly or indirectly, take any
action with respect to the Transfer Restricted Securities as a class that would adversely affect the ability of the Holders of Transfer Restricted Securities to include such Transfer Restricted Securities in a registration undertaken pursuant to
this Agreement. 
  
 (c) No Inconsistent Agreements. The
Issuer will not, on or after the date of this Agreement, 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. In
addition, the Issuer shall not grant to any of its security holders (other than the holders of Transfer Restricted Securities in such capacity) the right to include any of its securities in the Shelf Registration Statement provided for in this
Agreement other than the Transfer Restricted Securities. Other than the Rights Agreement, dated June 1, 2001, between the Company and Mellon Investor Services LLC., the Issuer has not previously entered into any agreement (which has not expired
or been terminated) granting any registration rights with respect to its securities to any Person which rights conflict with the provisions hereof. 
  
 (d) Amendments and Waivers. This Agreement may not be amended, modified or supplemented, and waivers or consents to or departures from the
provisions hereof may not be given, unless the Issuer has obtained the written consent of a Majority of Holders. 
  
 (e) Notices. All notices and other communications provided for or permitted hereunder shall be made in writing by hand-delivery, first-class mail
(registered or certified, return receipt requested), telex, telecopier, or air courier guaranteeing overnight delivery: 
  
 (i) if to a Holder, at the address set forth on the records of the registrar under the Indenture or the transfer agent of the Common
Stock, as the case may be; and 
  
 (ii) if to the
Issuer: 
  
 Nektar Therapeutics 
 150 Industrial Road 
 San Carlos, California 94070 
 Attention: Secretary 
  
 With a copy to: 
  

Cooley Godward LLP 
 Five Palo Alto Square 
 3000 El Camino Real Palo 
 Alto, CA 94306 Attention: John Geschke, Esq. 
  
 All such notices and communications shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; five Business Days
after being deposited in the 
  

 17 

 mail, postage prepaid, if mailed; when answered back, if telexed; when receipt acknowledged, if telecopied; and on the
next Business Day, if timely delivered to an air courier guaranteeing overnight delivery. 
  
 (f) Successors and Assigns. This Agreement shall inure to the benefit of and be binding upon the successors and assigns of each of the parties, including without limitation and without the need for an express
assignment, subsequent Holders of Transfer Restricted Securities; provided, however, that (i) this Agreement shall not inure to the benefit of or be binding upon a successor or assign of a Holder unless and to the extent such successor or
assign acquired Transfer Restricted Securities from such Holder and (ii) nothing contained herein shall be deemed to permit any assignment, transfer or other disposition of Transfer Restricted Securities in violation of the terms of the
Purchase Agreement or the Indenture. If any transferee of any Holder shall acquire Transfer Restricted Securities, in any manner, whether by operation of law or otherwise, such Transfer Restricted Securities shall be held subject to all of the terms
of this Agreement, and by taking and holding such Transfer Restricted Securities such person shall be conclusively deemed to have agreed to be bound by and to perform all of the terms and provisions of this Agreement. 
  
 (g) Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which when so executed shall be deemed to be an original and all of which taken together shall constitute one and the same agreement. 
  
 (h) Securities Held by the Issuer or Their Affiliates. Whenever the
consent or approval of Holders of a specified percentage of Transfer Restricted Securities is required hereunder, Transfer Restricted Securities held by the Issuer or its “affiliates” (as such term is defined in Rule 405 under the
Securities Act) shall not be counted in determining whether such consent or approval was given by the Holders of such required percentage. 
  
 (i) Headings. The headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning hereof.

  
 (j) Governing Law. This Agreement shall be governed by,
and construed in accordance with, the law of the State of New York, without regard to conflict of laws principles thereof. 
  
 (k) Severability. If any one or more of the provisions contained herein, or the application thereof in any circumstance, is held invalid, illegal
or unenforceable, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions contained herein shall not be affected or impaired thereby. 
  
 (l) Entire Agreement. This Agreement is intended by the parties as a
final expression of their agreement and intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. There are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein with respect to the registration rights granted by the Issuer with respect to the Transfer Restricted Securities. This Agreement supersedes all prior agreements and understandings
between the parties with respect to such subject matter. 
  

 18 

 IN WITNESS WHEREOF, the parties have executed this Agreement as of the date first written above.

  

			
	NEKTAR THERAPEUTICS
		
	By:	 	 /s/ Ajit Gill

	Name:	 	Ajit Gill
	Title:	 	Chief Executive Officer

  

 19 

			
	 MERRILL LYNCH, PIERCE, FENNER & SMITH
                         INCORPORATED

		
	By:	 	 /s/ Saira Ramasastry

	 	 	Authorized Representative
	
	LEHMAN BROTHERS INC.
		
	By:	 	 /s/ David A. Galper

	Name:	 	David A. Galper
	Title:	 	Vice President
	
	 For themselves and as representatives of the
 other Initial Purchasers

  

 20 

 Exhibit A 
  

NEKTAR THERAPEUTICS 
  
 THIS NOTICE AND QUESTIONNAIRE MUST BE RETURNED TO NEKTAR THERAPEUTICS (AT THE ADDRESS LISTED BELOW) ON OR BEFORE THE 20TH BUSINESS DAY FOLLOWING DELIVERY OF THE NOTICE AND QUESTIONNAIRE BY NEKTAR THERAPEUTICS TO THE TRUSTEE AND THE REGISTERED HOLDER IN ORDER TO BE NAMED IN THE
SHELF REGISTRATION STATEMENT REFERRED TO BELOW AT THE TIME OF ITS EFFECTIVENESS. 
  
 Form of Selling Securityholder Notice and Questionnaire 
  
 The undersigned beneficial holder of 3.25% Convertible Subordinated Notes due 2012 (the “Notes”) of Nektar Therapeutics (the “Company”), or shares of common stock, par value $0.0001 per share, of
the Company issuable upon conversion thereof (the “Conversion Shares” and together with the Notes, the “Transfer Restricted Securities”) understands that the Company has filed or intends to file with the Securities and Exchange
Commission (the “SEC”) a registration statement on Form S-3 (the “Shelf Registration Statement”), for the registration and resale under Rule 415 of the Securities Act of 1933, as amended (the “Securities Act”), of the
Transfer Restricted Securities in accordance with the terms of the Registration Rights Agreement, dated as of September 28, 2005 (the “Registration Rights Agreement”) among the Company and the initial purchasers named therein. A copy
of the Registration Rights Agreement is available from the Company upon request at the address set forth below. All capitalized terms not otherwise defined herein have the meaning ascribed thereto in the Registration Rights Agreement. 
  
 Each beneficial owner of Transfer Restricted Securities is entitled to the
benefits of the Registration Rights Agreement. In order to sell or otherwise dispose of any Transfer Restricted Securities pursuant to the Shelf Registration Statement, a beneficial owner of Transfer Restricted Securities generally will be required
to be named as a selling securityholder in the related prospectus, deliver a prospectus to purchasers of Transfer Restricted Securities and be bound by those provisions of the Registration Rights Agreement applicable to such beneficial owner
(including certain indemnification provisions, as described below). The Company will distribute this questionnaire to each holder. Beneficial owners must complete and deliver the Notice and Questionnaire within 20 business days of receipt so that
such beneficial owners may be named as selling securityholders in the related prospectus at the time of effectiveness. Upon receipt of a completed Notice and Questionnaire from a beneficial owner following the effectiveness of the Shelf Registration
Statement, the Company will, (i) if permitted by the SEC to file a prospectus supplement, file such supplements to the related prospectus within 15 business days’ receipt of the completed questionnaire and (2) within 30 days’
receipt of such completed questionnaire, file such amendments to the Shelf Registration Statement as are necessary to permit such holder to be named as a selling securityholder in such prospectus; provided that if an amendment to the Shelf
Registration Statement is required, the Company shall not be obligated to file such amendment unless the Company shall have received Notice and Questionnaires from holders of Transfer Restricted Securities holding an aggregate of at least
$10,000,000 principal amount of 
  

 1 

 Notes and in no event shall the Company be required to file more than one such amendment for all such holders in any one
fiscal quarter. The Company has agreed to pay additional interest pursuant to the Registration Rights Agreement under certain circumstances as set forth therein. 
  
 Certain legal consequences arise from being named as a selling securityholder in the Shelf Registration Statement and the
related prospectus. Accordingly, holders and beneficial owners of Transfer Restricted Securities are advised to consult their own securities law counsel regarding the consequences of being named or not being named as a selling securityholder in the
Shelf Registration Statement and the related prospectus. 
  
 Notice 
  
 The undersigned beneficial owner (the
“Selling Securityholder”) of Transfer Restricted Securities hereby gives notice to the Company of its intention to sell or otherwise dispose of Transfer Restricted Securities beneficially owned by it and listed below in Item 3 (unless
otherwise specified under Item 3) pursuant to the Shelf Registration Statement. The undersigned, by signing and returning this Notice and Questionnaire, understands that it will be bound by the terms and conditions of this Notice and
Questionnaire and the Registration Rights Agreement. 
  
 Pursuant
to the Registration Rights Agreement, the undersigned has agreed to indemnify and hold harmless the Company, the Company’s directors, officers and employees and each person, if any, who controls the Company within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against certain losses arising in connection with statements concerning the undersigned made in the Shelf Registration Statement or the related prospectus in
reliance upon the information provided in this Notice and Questionnaire. 
  
 The undersigned hereby provides the following information to the Issuer and represents and warrants that such information is accurate and complete: 
  
 Questionnaire 
  

	1.	(a)     Full legal name of Selling Securityholder: 

  
 ______________________________________________________________________________________________________________________________ 
  

	 	(b)	Full legal name of registered holder (if not the same as (a) above) through which Transfer Restricted Securities listed in (3) below are held: 

  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

 2 

	 	(c)	Full legal name of DTC participant (if applicable and if not the same as (b) above) through which Transfer Restricted Securities listed in (3) are held:

  
 ______________________________________________________________________________________________________________________________ 
  

	2.	Address for notices to Selling Securityholders: 

  
 Telephone:
                                        
                                        
                                        
                                        
         
  
 Fax:
                                        
                                        
                                        
                                        
                       
  
 Email:
                                        
                                        
                                        
                                        
                 
  
 Contact Person:
                                        
                                        
                                        
                                        

  

	3.	Beneficial ownership of Securities: 

  

	 	(a)	Type and Principal Amount of Transfer Restricted Securities beneficially owned: 

  
 ______________________________________________________________________________________________________________________________ 
  

	 	(b)	CUSIP No(s). of such Transfer Restricted Securities beneficially owned: 

  
 ______________________________________________________________________________________________________________________________ 
  

	 	(c)	Were the securities listed in Item 3(a) above acquired in the ordinary course of business? 

  
  ̈    Yes. 
  
  ̈    No. 
  
 ______________________________________________________________________________________________________________________________ 
  

	 	(d)	At the time of the purchase of the securities listed in Item 3(a) above, did the Selling Securityholder have any agreements or understandings, directly or indirectly, with any
person to distribute the securities? 

  
  ̈    Yes. 
  
  ̈    No. 
  

	 	(e)	If your response to Item 3(d) above is yes, please describe such agreements or understandings: 

  
 ______________________________________________________________________________________________________________________________ 
  

 3 

	4.	Beneficial ownership of other Company’s securities owned by the Selling Securityholder: 

  
 Except as set forth below in this Item 4, the undersigned is not the beneficial or registered owner of any
securities of the Company other than the Transfer Restricted Securities listed above in Item 3 (“Other Securities”). 
  

	 	(a)	Type and amount of Other Securities beneficially owned by the Selling Securityholder: 

  
 ______________________________________________________________________________________________________________________________ 
  

	 	(b)	CUSIP No(s). of such Other Securities beneficially owned: 

  
 ______________________________________________________________________________________________________________________________ 
  

	5.	(a)    Broker-Dealer Status: 

  
         Is the Selling Securityholder a registered broker-dealer? 
  
  ̈    Yes. 
  
  ̈    No. 
  
 Note that in general we will be required to identify any registered broker-dealer as an underwriter in the prospectus. 
  
 Is so, please answer the remaining questions in this section. 
  

	 	(i)	If the undersigned is a registered broker-dealer, please indicate whether the undersigned purchased its Transfer Restricted Securities for investment or acquired them as
transaction-based compensation for investment banking or similar services. 

  
 ______________________________________________________________________________________________________________________________ 
  

______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 If the undersigned is a registered broker-dealer and received its Transfer Restricted Securities other than as transaction-based compensation, the Company
is required to identify you as an underwriter in the Shelf Registration Statement and related Prospectus. 
  

	 	(ii)	Except as set forth below, if the undersigned is a registered broker-dealer, the undersigned does not plan to make a market in the Transfer Restricted Securities. If the undersigned
plans to make a market in the Transfer Restricted Securities, please indicate whether you plan to use the prospectus relating to the Transfer Restricted Securities as a market-making prospectus. 

  

 4 

 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

	 	(b)	Affiliation with Broker-Dealers: 

  
 Is the Selling Securityholder an affiliate of a registered broker-dealer? For purposes of this Item 5(b) an “affiliate” of a specified
person or entity means a person or entity that directly, or indirectly through one or more intermediaries, controls or is controlled by, or is under common control with the person or entity specified. 
  
  ̈    Yes. 
  
  ̈    No. 
  
 If so, please answer the remaining questions in this section. 
  

	 	(i)	Please describe the affiliation between the Selling Securityholder and any registered broker-dealers: 

  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

	 	(ii)	If the Notes were purchased by the Selling Securityholder other than in the ordinary course of business, please describe the circumstances: 

  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

	 	(iii)	If the Selling Securityholder, at the time of its purchase of Transfer Restricted Securities, has had any agreements or understandings, directly or indirectly, with any person to
distribute the Transfer Restricted Securities, please describe such agreements or understandings: 

  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

 5 

 ______________________________________________________________________________________________________________________________ 
  
 Note that if the Selling Securityholder is an affiliate of a broker-dealer and did not purchase its Notes in the ordinary course of business or at the
time of the purchase had any agreements or understandings, directly or indirectly, to distribute the securities, we much identify the Selling Securityholder as an underwriter in the prospectus. 
  

	6.	Relationship with the Company 

  
 Except as set forth below, neither the undersigned nor any of its affiliates, officers, directors or principal equity holders (5% or more) has held any
position or has had any other material relationship with the Company (or its predecessors or affiliates) during the past three years. 
  
 State any exceptions here: 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  

	7.	Nature of Beneficial Ownership. The purpose of this question is to identify the ultimate natural person(s) or publicly held entity that exercise(s) sole or shared voting or
dispositive power over the Transfer Restricted Securities. 

  

	 	(a)	Is the Selling Securityholder a natural person? 

  
  ̈    Yes. 
  
  ̈    No. 
  

	 	(b)	Is the Selling Securityholder required to file, or is it a wholly-owned subsidiary of a company that is required to file, periodic and other reports (for example, Forms 10-K, 10-Q,
8-K) with the SEC pursuant to Section 13(a) and 15(d) of the Exchange Act? 

  
  ̈    Yes. 
  
  ̈    No. 
  

	 	(c)	If you answered “No” to both questions above, please identify the controlling person(s) of the Selling Secuirtyholder (the “Controlling Entity”). If the
Controlling Entity is not a natural person or a publicly held entity, please identify each controlling person(s) of such Controlling Entity. This process should be repeated until you reach natural persons or a publicly held entity that exercise sole
or shared voting or dispositive power over the Transfer Restricted Securities. 

  

 6 

 ______________________________________________________________________________________________________________________________ 
  
 If you need more space for this response, please attach additional sheets of paper. Please be sure to indicate your name and the number of the item
being responded to on each such additional sheet of paper, and to sign each such additional sheet of paper before attaching it to this Questionnaire. Please note that you may be asked to answer additional questions depending on your responses to the
above questions. 
  

	8.	Plan of Distribution: 

  
 Except as set forth below, the undersigned (including its donees or pledgees) intends to distribute the Transfer Restricted Securities listed above in
Item 3 pursuant to the Shelf Registration Statement only as follows (if at all): Such Transfer Restricted Securities may be sold from time to time directly by the undersigned or, alternatively, through underwriters, broker-dealers or agents. If
the Transfer Restricted Securities are sold through underwriters or broker-dealers, the Selling Securityholder will be responsible for underwriting discounts or commissions or agent’s commissions. Such Transfer Restricted Securities may be sold
in one or more transactions at fixed prices, at prevailing market prices at the time of sale, at varying prices determined at the time of sale, or at negotiated prices. Such sales may be effected in transactions (which may involve crosses or block
transactions), (i) on any national securities exchange or quotation service on which the Transfer Restricted Securities may be listed or quoted at the time of sale, (ii) in the over-the-counter market or, (iii) in transactions
otherwise than on such exchanges or services or in the over-the-counter market. 
  
 State any exceptions here: 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 Note: In no event will such method(s) of distribution take the form of an underwritten offering of the Transfer Restricted Securities without the prior agreement of the
Issuer. 
  

	9.	Securities Received From Named Selling Securityholder: 

  
 Did the Selling Securityholder receive its Transfer Restricted Securities listed above in Item 3 as a transferee from selling securityholder(s)
previously identified in the Shelf Registration Statement? 
  
  ̈    Yes. 
  
  ̈    No. 
  
 If so, please answer the remaining questions in this section. 
  

 7 

	 	(i)	Did the Selling Securityholder receive such Transfer Restricted Securities listed above in Item 3 from the named selling securityholder(s) prior to the effectiveness of the
Shelf Registration Statement? 

  
  ̈    Yes. 
  
  ̈    No. 
  

	 	(ii)	Identify below the name(s) of the selling securityholder(s) from whom the Selling Securityholder received the Transfer Restricted Securities listed above in Item 3 and the date
on which such securities were received. 

  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 ______________________________________________________________________________________________________________________________ 
  
 The undersigned acknowledges that it understands its obligation to comply with the provisions of the Exchange Act and the rules and regulations thereunder
relating to stock manipulation, particularly Regulation M thereunder (or any successor rules or regulations), in connection with any offering of Transfer Restricted Securities pursuant to the Shelf Registration Statement. 
  
 The undersigned agrees that neither it nor any person acting on its behalf
will engage in any transaction in violation of such provisions. 
  
 The Selling Securityholder hereby acknowledges its obligations under the Registration Rights Agreement, including, without limitation, its obligations to indemnify and hold harmless certain persons and to comply with its prospectus delivery
requirements as set forth therein. 
  
 Pursuant to the
Registration Rights Agreement, the Company has agreed under certain circumstances to indemnify the Selling Securityholders against certain liabilities. 
  
 In accordance with the undersigned’s obligation under the Registration Rights Agreement to provide such information as may be required by law for
inclusion in the Shelf Registration Statement, the undersigned agrees to promptly notify the Issuer of any inaccuracies or changes in the information provided herein that may occur subsequent to the date hereof at any time while the Shelf
Registration Statement remains effective. All notices hereunder and pursuant to the Registration Rights Agreement shall be made in writing at the address set forth below. 
  
 In the event that the undersigned transfers all or any portion of the Transfer Restricted Securities listed in Item 3
above after the date on which such information is provided to the Company, the undersigned agrees to notify the transferee(s) at the time of transfer of its rights and obligations under this Notice and Questionnaire and the Registration Rights
Agreement. 
  
 By signing below, the undersigned consents to the
disclosure of the information contained herein in its answers to Items 1 through 8 above and the inclusion of such information 

  

 8 

 
in the Shelf Registration Statement and the related prospectus. The undersigned understands that such information will be relied upon by the Company in
connection with the preparation or amendment of the Shelf Registration Statement and the related prospectus. 
  
 Once this Notice and Questionnaire is executed by the undersigned beneficial holder and received by the Company, the terms of this Notice and
Questionnaire, and the representations and warranties contained herein, shall be binding on, shall inure to the benefit of and shall be enforceable by the respective successors, heirs, personal representatives and assigns of the Company and the
undersigned beneficial holder. This Notice and Questionnaire shall be governed in all respects by the laws of the State of New York. 
  

 9 

 IN WITNESS WHEREOF, the undersigned, by authority duly given, has caused this Notice and Questionnaire to
be executed and delivered either in person or by its duly authorized agent. 
  

			
	Beneficial Owner:	 	  

  

			
	By:	 	  

	Name:	 	 
	Title:	 	 
		
	Dated:	 	  

  
 PLEASE RETURN THE COMPLETED AND
EXECUTED NOTICE AND QUESTIONNAIRE TO NEKTAR THERAPEUTICS NO LATER THAN THE 20TH BUSINESS DAY AFTER THIS NOTICE AND
QUESTIONNAIRE HAS BEEN DELIVERED TO THE TRUSTEE AND THE REGISTERED HOLDER AT: 
  
                                        
             Nektar Therapeutics 
                                        
             150 Industrial Road 
                                        
             San Carlos, California 94070 
                                        
             Attention: Secretary 
                                        
             Telephone: (650) 631-3100 
                                        
             Facsimile: (650) 631-3150 
  

 10Purchase Agreement

 Exhibit 10.1 
  
 NEKTAR THERAPEUTICS 
 (a Delaware corporation) 
  
 $275,000,000 
 3.25% Convertible Subordinated Notes due 2012 
  
 PURCHASE AGREEMENT 
  
 September 22, 2005 

	Merrill	Lynch, Pierce, Fenner & Smith 

 Incorporated

 4 World Financial Center 
 New York, New York 10080 

 
 Lehman Brothers Inc. 
 745 Seventh Avenue 
 New York, New York 10019 
     As Representatives of the several Initial Purchasers 
  
 Ladies and Gentlemen: 
  
 Nektar
Therapeutics, a Delaware corporation (the “Company”), confirms its agreement with each of the Initial Purchasers named in Schedule 1 hereto (collectively, the “Initial Purchasers,” which term shall also include any initial
purchaser substituted as hereinafter provided in Section 8 hereof), for whom Merrill Lynch, Pierce, Fenner & Smith Incorporated and Lehman Brothers Inc. are acting as representatives (in such capacity, the “Representatives”), with
respect to the issue and sale by the Company and the purchase by the Initial Purchasers, acting severally and not jointly, of the respective principal amounts set forth in said Schedule 1 of $275,000,000 aggregate principal amount of the
Company’s 3.25% Convertible Subordinated Notes due 2012 (the “Firm Notes”), and with respect to the grant by the Company to the Initial Purchasers, acting severally and not jointly, of the option described in Section 2(b) hereof (the
“Option”) to purchase all or any part of an additional $40,000,000 principal amount of the Company’s 3.25% Convertible Subordinated Notes due 2012 (the “Optional Notes” and, together with the Firm Notes, the
“Notes”). 
  
 The Notes will be convertible into fully
paid, nonassessable shares of common stock of the Company, par value $0.0001 per share (the “Common Stock”), on the terms, and subject to the conditions, set forth in the Indenture (as defined below). As used herein, “Conversion
Shares” means the shares of Common Stock into which the Notes are convertible. The Notes will be issued pursuant to an Indenture (the “Indenture”) to be dated as of the First Delivery Date (as defined in Section 2(a)), between the
Company and J.P. Morgan Trust Company, National Association, as trustee (the “Trustee”). 

 The Notes will be offered and sold without being registered under the Securities Act of 1933, as amended
(the “Securities Act”), in reliance on exemptions therefrom. The Company has prepared and delivered to each Initial Purchaser copies of a preliminary offering memorandum dated September 21, 2005 (the “Preliminary Offering
Memorandum”) and has prepared and will deliver to each Initial Purchaser, on the date hereof or the next succeeding day, copies of a final offering memorandum dated September 22, 2005 (the “Final Offering Memorandum”), each for use by
such Initial Purchaser in connection with its solicitation of purchases of, or offering of, the Notes. “Offering Memorandum” means, with respect to any date or time referred to in this Agreement, the most recent offering memorandum
(whether the Preliminary Offering Memorandum or the Final Offering Memorandum, or any amendment or supplement to either such document) which has been prepared and delivered by the Company to the Initial Purchasers in connection with their
solicitation of purchases of, or offering of, the Notes. As used herein, the terms “Preliminary Offering Memorandum,” “Final Offering Memorandum” and “Offering Memorandum” shall include in each case the documents
incorporated by reference therein. 
  
 Holders of the Notes
(including the Initial Purchasers and their direct and indirect transferees) will be entitled to the benefits of a Resale Registration Rights Agreement, dated the First Delivery Date, between the Company and the Initial Purchasers (the
“Registration Rights Agreement”), pursuant to which the Company will agree to file with the Securities and Exchange Commission (the “Commission”) a shelf registration statement pursuant to Rule 415 under the Securities Act (the
“Registration Statement”) covering the resale of the Notes and the Conversion Shares, and to use its best efforts to cause the Registration Statement to be declared effective. 
  
 This Agreement, the Indenture, the Notes and the Registration Rights Agreement are referred to herein collectively as the
“Operative Documents.” 
  
 Capitalized terms used herein
without definition have the respective meanings specified in the Offering Memorandum. 
  
 1. Representations, Warranties and Agreements of the Company. The Company represents and warrants to each Initial Purchaser as of the date hereof and as of each Delivery Date (as defined in Section 2(b)) and
agrees with each Initial Purchaser, as follows: 
  
 (a) Each of the Preliminary Offering Memorandum and the Offering Memorandum, did not as of its respective date, and the Offering Memorandum will not as of a Delivery Date (as defined in Section 2(b)), contain any untrue statement of a
material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation or warranty as
to information contained in or omitted from the Preliminary 
  

 2 

 Offering Memorandum or the Offering Memorandum in reliance upon and in conformity with written
information furnished to the Company by or on the behalf of any Initial Purchaser through the Representatives specifically for inclusion therein. 
  
 (b) Assuming the accuracy of the representations and warranties of the Initial Purchasers contained in Section 6 and their compliance with
the agreements set forth therein, it is not necessary, in connection with the issuance and sale of the Notes to the Initial Purchasers and the offer, resale and delivery of the Notes by the Initial Purchasers in the manner contemplated by this
Agreement, the Indenture, the Registration Rights Agreement and the Offering Memorandum, to register the Notes or the Conversion Shares under the Securities Act or to qualify the Indenture under the Trust Indenture Act of 1939, as amended (the
“Trust Indenture Act”). 
  
 (c) The
Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Delaware, is duly qualified to do business and is in good standing as a foreign corporation in each jurisdiction in which its
ownership or lease of property or the conduct of its businesses requires such qualification (except for where the failure to be so qualified would not have a material adverse effect on the affairs, management, business, properties, financial
condition, results of operations or prospects of the Company and its subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business (a “Material Adverse Effect”)), and has all power and authority
necessary to own or hold its properties and to conduct the businesses in which it is engaged, as described in the Offering Memorandum. 
  
 (d) Each subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of
its jurisdiction of incorporation, is duly qualified to do business and is in good standing as a foreign corporation in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such qualification
(except for where the failure to be so qualified would not have a Material Adverse Effect) and has all power and authority necessary to own or hold its properties and to conduct the businesses in which it is engaged, as described in the Offering
Memorandum; except as otherwise disclosed in the Offering Memorandum, all of the issued and outstanding capital stock of each subsidiary of the Company has been duly authorized and validly issued, is fully paid and non-assessable and is owned by the
Company, directly or through subsidiaries, free and clear of any security interest, mortgage, pledge, lien, encumbrance, claim or equity; none of the outstanding shares of capital stock of any such subsidiary was issued in violation of the
preemptive or similar rights of any securityholder of such subsidiary. 
  
 (e) The authorized, issued and outstanding capital stock of the Company, as of June 30, 2005, is as set forth in the Offering Memorandum under the column entitled “Actual” under the caption
“Capitalization,” and all of the issued and outstanding shares of capital stock of the Company have been duly 
  

 3 

 authorized and validly issued, and are fully paid and nonassessable; none of the outstanding shares of
capital stock of the Company was issued in violation of the preemptive or other similar rights of any securityholder of the Company; the capital stock of the Company conforms to the description thereof contained in the Offering Memorandum and such
description conforms to the rights set forth in the instruments defining the same; the Conversion Shares, which are authorized on the date hereof, have been duly authorized and reserved for issuance upon conversion of the Notes by all necessary
corporate action and are free of preemptive rights; all Conversion Shares, when so issued and delivered upon such conversion in accordance with the terms of the Indenture, will be duly authorized and validly issued, fully paid and nonassessable and
free and clear of all liens, encumbrances, equities or claims; and the issuance of such Conversion Shares upon such conversion will not be subject to the preemptive or other similar rights of any securityholder of the Company. 
  
 (f) The execution, delivery and performance of the Operative
Documents by the Company and the issuance of the Notes and the Conversion Shares and the consummation of the transactions contemplated hereby and thereby will not (x) conflict with or result in a breach or violation of any of the terms or provisions
of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which it or any of them are bound or to which any of the
properties or assets of the Company or any subsidiary is subject, (y) result in any violation of the provisions of the certificate of incorporation or bylaws of the Company or any of its subsidiaries or (z) result in any violation of any statute or
any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any subsidiary or any of their properties or assets; and except (i) with respect to the transactions contemplated by the Registration
Rights Agreement, as may be required under the Securities Act, the Trust Indenture Act and the rules and regulations promulgated thereunder and (ii) as required by the state securities or “blue sky” laws, no consent, approval,
authorization or order of, or filing or registration with, any such court or governmental agency or body is required for the execution, delivery and performance of the Operative Documents by the Company, and the consummation of the transactions
contemplated hereby and thereby. 
  
 (g) The
Company has all necessary corporate right, power and authority to execute and deliver this Agreement and perform its obligations hereunder; and this Agreement has been duly authorized, executed and delivered by the Company and the transactions
contemplated hereby have been duly authorized by the Company. 
  
 (h) The Company has all necessary corporate right, power and authority to execute and deliver the Indenture and perform its obligations thereunder; the Indenture has been duly authorized by the Company, and upon the
effectiveness of the Registration Statement, will be qualified under the Trust 
  

 4 

 Indenture Act; on the First Delivery Date, the Indenture will have been duly executed and delivered by
the Company and, assuming due authorization, execution and delivery of the Indenture by the Trustee, will constitute a legally valid and binding agreement of the Company enforceable against the Company in accordance with its terms, except as the
enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally, subject to general principles of equity and to
limitations on availability of equitable relief, including specific performance (whether considered in a proceeding in equity or at law) and an implied covenant of good faith and fair dealing; and the Indenture conforms in all material respects to
the description thereof contained in the Offering Memorandum. 
  
 (i) The Company has all necessary corporate right, power and authority to execute and deliver the Registration Rights Agreement and perform its obligations thereunder; the Registration Rights Agreement and the
transactions contemplated thereby have been duly authorized by the Company; when the Registration Rights Agreement is duly executed and delivered by the Company (assuming due authorization, execution and delivery by the Initial Purchasers), it will
be a legally valid and binding agreement of the Company enforceable against the Company in accordance with its terms, except as the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and
other similar laws relating to or affecting creditors’ rights generally, subject to general principles of equity and to limitations on availability of equitable relief, including specific performance (whether considered in a proceeding in
equity or at law) and an implied covenant of good faith and fair dealing, and except with respect to the rights of indemnification and contribution thereunder, where enforcement thereof may be limited by federal or state securities laws or the
policies underlying such laws; and the Registration Rights Agreement conforms in all material respects to the description thereof contained in the Offering Memorandum. 
  
 (j) The Company has all necessary corporate right, power and authority to execute, issue and deliver the
Notes and perform its obligations thereunder; the Notes have been duly authorized by the Company; when the Notes are executed, authenticated and issued in accordance with the terms of the Indenture and delivered to and paid for by the Initial
Purchasers pursuant to this Agreement on the respective Delivery Date (assuming due authentication of the Notes by the Trustee), such Notes will constitute legally valid and binding obligations of the Company, entitled to the benefits of the
Indenture and enforceable against the Company in accordance with their terms, except as the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and other similar laws relating to or
affecting creditors’ rights generally, subject to general principles of equity and to limitations on availability of equitable relief, including specific performance (whether considered in a proceeding in equity or at law) and an implied
covenant of good faith and fair dealing; and the Notes conform in all material respects to the description thereof contained in the Offering Memorandum. 
  

 5 

 (k) Except for the Rights Agreement, dated June 1, 2001, between the Company and Mellon
Investor Services LLC., there are no contracts, agreements or understandings between the Company and any person granting such person the right (other than rights which have been waived or satisfied) to require the Company to file a registration
statement under the Securities Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in any securities being registered pursuant to any registration statement filed
by the Company under the Securities Act. 
  
 (l)
Neither the Company nor any of its subsidiaries has sustained, since the date of the latest audited financial statements included in the Offering Memorandum, any material loss or interference with its business from fire, explosion, flood or other
calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree; and, since such date, there has not been any change in the capital stock or long-term debt of the Company or any of its
subsidiaries (except for (i) any grants under the Company’s employee stock plans in accordance with the terms of such plans as described in the Offering Memorandum, or other shares of Common Stock (or rights to receive Common Stock) issued to
service providers to the Company in the ordinary course of business (“Authorized Grants”), (ii) the issuance of common stock upon conversion of outstanding convertible securities or exercise of any outstanding rights to acquire common
stock pursuant to the Company’s employee stock plans as described in the Offering Memorandum (“Authorized Issuances”) and (iii) indebtedness incurred by the Company’s subsidiaries pursuant to outstanding lines of credit or other
debt facilities not to exceed $10.0 million), or any material adverse change in or affecting the affairs, management, business, properties, financial condition, stockholders’ equity, results of operations or prospects of the Company and its
subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business, except in all cases as described in the Offering Memorandum. 
  
 (m) The financial statements of the Company and its consolidated subsidiaries (including the related notes
and supporting schedules) included in the Offering Memorandum present fairly the financial condition and results of operations of the Company and its consolidated subsidiaries, at the dates and for the periods indicated, and have been prepared in
conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved. The selected and summary financial information, if any, included in the Offering Memorandum presents fairly the information shown
therein and has been compiled on a basis consistent with that of the audited financial statements included in the Offering Memorandum. 
  
 (n) Ernst & Young LLP, who certified the financial statements and supporting schedules, if any, of the Company included in the
Offering Memorandum, are an independent registered public accounting firm as required by the Securities Act and the rules and regulations promulgated thereunder. 
  

 6 

 (o) The Company and its subsidiaries have good and marketable title in fee simple to all
real property and good and marketable title to all personal property owned by them, in each case free and clear of all liens, encumbrances, security interests, claims and defects, except such as are described in the Offering Memorandum or such as do
not, singly or in the aggregate, materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company or any of its subsidiaries; and all real property and personal property held
under lease or sublease by the Company and its subsidiaries is held by them under valid, subsisting and enforceable leases (or subleases, as the case may be) in full force and effect, with such exceptions as are not material and do not interfere
with the use made and proposed to be made of such property by the Company or any of its subsidiaries. Neither the Company nor any of its subsidiaries have notice of any material claim of any sort that has been asserted by anyone adverse to the
rights of the Company or any of its subsidiaries under any of the leases or subleases mentioned above, or affecting or questioning the rights of the Company or such subsidiary to the continued possession of the leased or subleased premises under any
such lease or sublease. 
  
 (p) The Company and
its subsidiaries carry, or are covered by, insurance as is customary for companies similarly situated and engaged in similar businesses in similar industries. 
  

(q) The Company and its subsidiaries own, or possess adequate rights to use, all material trademarks, service marks, trade names,
trademark registrations, service mark registrations, copyrights and licenses necessary for the conduct of their business, and have no reason to believe that the conduct of their business will conflict with, and have not received any notice of any
claim of conflict with, any such rights of others. 
  
 (r) The Company and its subsidiaries own, or possess adequate rights to use, all material patents necessary for the conduct of their business. Except as set forth in the Offering Memorandum, no valid U.S. patent is, or to the knowledge of
the Company would be, infringed by the activities of the Company or any of its subsidiaries in the manufacture, use, offer for sale or sale of any product or component thereof as described in the Offering Memorandum. The patent applications (the
“Patent Applications”) filed by or on behalf of the Company and its subsidiaries described in the Offering Memorandum have been properly prepared and filed on behalf of the Company and its subsidiaries; each of the Patent Applications and
patents (the “Patents”) described in the Offering Memorandum is assigned or licensed to the Company or its subsidiaries, and, except as set forth or contemplated in the Offering Memorandum, no other entity or individual has any right or
claim in any Patent, Patent Application or any patent to be issued therefrom; and, to the knowledge of the Company, each of the Patent Applications discloses potentially patentable subject matter. There are no 
  

 7 

 actions, suits or judicial proceedings pending relating to patents or proprietary information to which
the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is subject, and, to the knowledge of the Company, no actions, suits or judicial proceedings are threatened by governmental
authorities or, except as set forth or contemplated in the Offering Memorandum, or as could not individually or in the aggregate be reasonably expected to have a Material Adverse Effect. The Company is not aware of, except as set forth or
contemplated in the Offering Memorandum, any claim by others that the Company or any of its subsidiaries is infringing or otherwise violating any patents or other intellectual property rights of others and is not aware of any rights of third parties
to any of the Company’s or any of its subsidiaries’ Patent Applications, licensed Patents or licenses which could affect materially the use thereof by the Company or any of its subsidiaries. Except as set forth in the Offering Memorandum,
the Company and its subsidiaries own or possess sufficient licenses or other rights to use all patents, trade secrets, technology and know-how necessary to conduct their business as described in the Offering Memorandum. 
  
 (s) Except as disclosed in the Offering Memorandum, the
Company and its subsidiaries have filed with the Food and Drug Administration (the “FDA”) and the California Food and Drug Branch (“CFDB”) for and received approval of all registrations, applications, licenses, requests for
exemptions, permits and other regulatory authorizations necessary to conduct their business as it is described in the Offering Memorandum; the Company and its subsidiaries are in material compliance with all such registrations, applications,
licenses, requests for exemptions, permits and other regulatory authorizations, and all applicable FDA and CFDB rules and regulations, guidelines and policies, including but not limited to, applicable FDA and CFDB rules, regulations and policies
relating to current good manufacturing practice (“CGMP”) and current good laboratory practice (“CGLP”); the Company has no reason to believe that any party granting any such registration, application, license, request for
exemption, permit or other authorization is considering limiting, suspending or revoking the same and knows of no basis for any such limitation, suspension or revocation. 
  
 (t) The human clinical trials, animal studies and other preclinical tests conducted by the Company or any
subsidiary or in which the Company or any subsidiary has participated that are described in the Offering Memorandum or the results of which are referred to in the Offering Memorandum, and, to the knowledge of the Company, such studies and tests
conducted on behalf of the Company or any of its subsidiaries, were and, if still pending, are being conducted in accordance with commonly used or appropriate experimental protocols, procedures and controls applied by research scientists generally
in the preclinical or clinical study of new drugs; the descriptions or the results of such studies and tests contained in the Offering Memorandum are accurate and complete in all material respects, and the Company has no knowledge of any other
studies or tests, the results of which reasonably call into question the results of such studies and tests described or referred to in the Offering Memorandum; and neither the 
  

 8 

 Company nor any of its subsidiaries has received any notices or other correspondence from the FDA or any
other governmental agency requiring the termination, suspension or modification of any animal studies or other preclinical tests, or clinical studies conducted by or on behalf of the Company or any of its subsidiaries or in which the Company or any
of its subsidiaries has participated that are described in the Offering Memorandum or the results of which are referred to in the Offering Memorandum. 
  
 (u) Except as disclosed in the Offering Memorandum, there are no legal or governmental proceedings pending to which the Company or any of
its subsidiaries is a party or of which any of their respective properties or assets is the subject which, if determined adversely to the Company or any subsidiary might have a Material Adverse Effect, or which might reasonably be expected to
materially and adversely affect the consummation of the transactions contemplated by this Agreement or the performance by the Company of its obligations hereunder; to the Company’s knowledge, no such proceedings are threatened or contemplated
by governmental authorities or, except as set forth or contemplated in the Offering Memorandum, threatened by others; and the aggregate of all pending legal or governmental proceedings to which the Company or any of its subsidiaries is a party or of
which any of their respective properties or assets is the subject (other than the Company’s or any subsidiary’s patent applications currently pending before the U.S. Patent and Trademark Office or before any foreign governmental authority
that administers the registration of patents), which are not described in the Offering Memorandum, including ordinary routine litigation incidental to the business, could not reasonably be expected to result in a Material Adverse Effect. 

 
 (v) No event has occurred nor has any circumstance arisen
which, had the Notes been issued on such Delivery Date, would constitute a default or an Event of Default (as such term is defined in the Indenture). 
  
 (w) Neither the Company nor any of its subsidiaries is (i) in violation of its certificate of incorporation or bylaws, (ii) in default,
and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or
other agreement or instrument to which the Company or any of its subsidiaries is a party or by which it or any of them may be bound or to which any of the properties or assets of the Company or any of its subsidiaries is subject or (iii) in
violation of any law, ordinance, governmental rule, regulation or court decree to which any properties or assets of the Company or any of its subsidiaries may be subject or has failed to obtain any license, permit, certificate, franchise or other
governmental authorization or permit necessary to the ownership of their properties or to the conduct of their business, except to the extent that any such default, event or violation described in the foregoing clauses (i), (ii) and (iii) would not
have a Material Adverse Effect. 
  

 9 

 (x) The Company is in compliance in all material respects with all presently applicable
provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder (“ERISA”); no “reportable event” (as defined in ERISA) has occurred with respect to
any “pension plan” (as defined in ERISA) for which the Company would have any liability; the Company has not incurred and does not expect to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from,
any “pension plan” or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the “Code”); and each “pension plan” for which the
Company would have any liability that is intended to be qualified under Section 401(a) of the Code is so qualified in all material respects and nothing has occurred, whether by action or by failure to act, which would cause the loss of such
qualification. 
  
 (y) The Company is subject to
the reporting requirements of Section 13 or Section 15(d) of the Exchange Act. The Company has timely and, except with respect to the failure to provide information with respect to certain change of control and severance arrangements with respect to
J. Milton Harris, which information was subsequently provided in an amendment to the Company’s Form 10-K for the year ended December 31, 2002 filed prior to the date of this Agreement, properly filed with the Commission all reports and other
documents required to have been filed by it with the Commission pursuant to the Exchange Act and the Exchange Act Regulations (“Exchange Act Reports”). 
  
 (z) The Company and each of its subsidiaries, if applicable, have filed all federal, state and local income
and franchise tax returns required to be filed through the date hereof or have requested extensions thereof and have paid all taxes due thereon, and no tax deficiency has been determined adversely to the Company which has had (nor does the Company
or any of its subsidiaries have any knowledge of any tax deficiency which, if determined adversely to the Company or any of its subsidiaries, might have) a Material Adverse Effect. 
  
 (aa) There has been no storage, disposal, generation, manufacture, refinement, transportation, handling or
treatment of toxic wastes, medical wastes, hazardous wastes or hazardous substances by the Company or any of its subsidiaries (or, to the knowledge of the Company, any predecessors in interest of the Company or any of its subsidiaries) at, upon or
from any of the property now or previously owned or leased by the Company or any of its subsidiaries in violation of any applicable law, ordinance, rule, regulation, order, judgment, decree or permit or which would require remedial action under any
applicable law, ordinance, rule, regulation, order, judgment, decree or permit, except for any violation or remedial action which would not have, or could not be reasonably likely to have, singularly or in the aggregate with all such violations and
remedial actions, a Material Adverse Effect; there has been no material spill, discharge, leak, emission, injection, escape, dumping or release of any kind onto such property or into the environment surrounding such property of any toxic wastes,

  

 10 

 medical wastes, solid wastes, hazardous wastes or hazardous substances due to or caused by the Company or
any of its subsidiaries or with respect to which the Company has knowledge, except for any such spill, discharge, leak, emission, injection, escape, dumping or release which would not have or would not be reasonably likely to have, singularly or in
the aggregate with all such spills, discharges, leaks, emissions, injections, escapes, dumpings and releases, a Material Adverse Effect; and the terms “hazardous wastes,” “toxic wastes,” “hazardous substances” and
“medical wastes” shall have the meanings specified in any applicable local, state, federal and foreign laws or regulations with respect to environmental protection. 
  
 (bb) There are no contracts or other documents which would be required to be described in the Offering
Memorandum if the Offering Memorandum were a prospectus included in a registration statement on Form S-1 that have not been so described in the Offering Memorandum. 
  
 (cc) There is no relationship, direct or indirect, between or among the Company or any of its subsidiaries,
on the one hand, and the directors, executive officers, shareholders, customers or suppliers of the Company or any of its subsidiaries, on the other hand, which would be required to be described in the Offering Memorandum if the Offering Memorandum
were a prospectus included in a registration statement on Form S-1 that has not been so described. 
  
 (dd) Since the date as of which information is given in the Offering Memorandum through the date hereof, the Company has not (i) issued or
granted any securities (other than Authorized Grants), (ii) incurred any material liability or obligation, direct or contingent, other than liabilities and obligations which were incurred in the ordinary course of business or referenced in Section
1(l)(iv) above, (iii) entered into any material transaction not in the ordinary course of business, other than as referenced in Section 1(l)(iv) above or (iv) declared or paid any dividend on its capital stock. 
  
 (ee) Except as disclosed in the Offering Memorandum, (i)
there are no outstanding securities convertible into or exchangeable for, or warrants, rights or options issued by the Company to purchase, any shares of the capital stock of the Company (except, in the case of options, any Authorized Grants or
Authorized Issuances), (ii) there are no statutory, contractual, preemptive or other rights to subscribe for or to purchase any Common Stock and (iii) there are no restrictions upon transfer of the Common Stock pursuant to the Company’s
certificate of incorporation or bylaws. 
  
 (ff)
Except as is limited by any material weakness in internal control over financial reporting disclosed in the Offering Memorandum, the Company (i) makes and keeps materially accurate books and records and (ii) maintains internal accounting controls
which provide reasonable assurance that (A) transactions are executed in accordance with management’s authorization, (B) transactions are recorded as necessary to permit preparation of its financial 
  

 11 

 statements and to maintain accountability for its assets, (C) access to its assets is permitted only in
accordance with management’s authorization and (D) the reported accountability for its assets is compared with existing assets at reasonable intervals. 
  
 (gg) Neither the Company or any of its subsidiaries nor any director, officer, agent or employee acting on behalf of the Company or any of
its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity, (ii) made any direct or indirect unlawful payment to any foreign or domestic government
official or employee from corporate funds, (iii) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977 or (iv) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment. 
  
 (hh) No labor disturbance by the employees of the Company or
any of its subsidiaries exists or, to the knowledge of the Company, is imminent which might be expected to have a Material Adverse Effect. 
  
 (ii) The Company is not, and upon the issuance and sale of the Notes as herein contemplated and the application of the net proceeds
therefrom as described in the Offering Memorandum will not be, an “investment company” or an entity “controlled” by an “investment company” as such terms are defined in the Investment Company Act of 1940, as amended.

  
 (jj) Assuming the accuracy of the
representations and warranties of the Initial Purchasers contained in Section 6 and their compliance with the agreements set forth therein, the Securities will be eligible for resale pursuant to Rule 144A. No securities of the same class (within the
meaning of Rule 144A(d)(3) under the Securities Act) as the Notes are listed on any national securities exchange registered under Section 6 of the Exchange Act or quoted on an automated inter-dealer quotation system. 
  
 (kk) None of the Company or any of its Affiliates (as
defined in Rule 501(b) of Regulation D under the Securities Act (“Regulation D”)) (other than the Initial Purchasers, about which no representation is made by the Company), has, directly or through an agent, engaged or will engage in any
form of general solicitation or general advertising in connection with the offering of the Notes (as those terms are used in Regulation D) under the Securities Act or in any manner involving a public offering within the meaning of Section 4(2) of
the Securities Act; the Company has not entered into any contractual arrangement with respect to the distribution of the Notes except for this Agreement and the Company will not enter into any such arrangement. 
  
 (ll) None of the Company or any of its affiliates (other
than the Initial Purchasers, about which no representation is made by the Company), has, directly or through any agent, sold, offered for sale, solicited offers to buy or otherwise negotiated in respect of, any “security” (as defined in
the Securities Act) which is or will be integrated with the sale of the Notes in a manner that would require the registration under the Securities Act of the Notes. 
  

 12 

 (mm) The Company has not taken, directly or indirectly, any action designed to cause or
result in, or which has constituted or which might reasonably be expected to constitute, the stabilization or manipulation of the price of any security of the Company in connection with the offering of the Notes. 
  
 (nn) No consent, approval or vote of the Company’s
shareholders is necessary or required in connection with the offering, issuance or sale of the Notes hereunder or, except as may be required under the Nasdaq National Market rules if the shares of Common Stock issuable upon conversion of the Notes
exceed 20% of the outstanding voting stock of the Company, the issuance of shares of Common Stock upon conversion of the Notes. 
  
 (oo) Nektar Alabama is the Company’s only subsidiary that, for and as of the end of the most recent year as to which audited
financial statements are included in the Offering Memorandum, had revenues or total assets that exceeded 10% of the Company’s consolidated revenues for such fiscal year or total assets as of the end of such fiscal year. 
  
 (pp) There is and has been no failure on the part of the
Company or any of the Company’s directors or officers, in their capacities as such, to comply in all material respects with any provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith,
including Section 402 related to loans and Sections 302 and 906 related to certifications. 
  
 2. Purchase, Sale and Delivery of Notes. 
  
 (a) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to each Initial Purchaser, and each Initial Purchaser agrees, severally and
not jointly, to purchase from the Company, at a purchase price of 97.15% of the principal amount thereof (the “purchase price”) the principal amount of Firm Notes set forth opposite such Initial Purchaser’s name in Schedule 1
hereto (or such number increased as set forth in Section 8). 
  
 Delivery of and payment for the Firm Notes shall be made at the office of Sidley Austin Brown & Wood LLP, 555 California Street, San Francisco, California 94104, at 10:00 a.m. (New York City time) on September 28, 2005,
or such later date as the Representatives shall designate, which date and time may be postponed by agreement between the Representatives and the Company or as provided in Section 8 (such date and time of delivery and payment for the Firm Notes being
herein called the “First Delivery Date”). Delivery of the Firm Notes shall be made to the Initial Purchasers against payment of the purchase price by the Initial Purchasers. Payment for the Firm Notes shall be effected either by wire
transfer of immediately available funds to an account with a bank in The City of New York, the account number and the ABA number for such bank 
  

 13 

 to be provided by the Company to the Representatives at least two business days in advance of the First Delivery Date, or
by such other manner of payment as may be agreed by the Company and the Representatives. It is understood that each Initial Purchaser has authorized the Representatives, for its account, to accept delivery of, issue a receipt for, and make payment
of the purchase price for, the Firm Notes that it has agreed to purchase. The Representatives, individually and not as representatives of the Initial Purchasers, may (but shall not be obligated to) make payment of the purchase price for the Firm
Notes to be purchased by any Initial Purchaser whose funds have not been received by the First Delivery Date but such payment shall not relieve such Initial Purchaser from its obligations hereunder. 
  
 (b) Subject to the terms and conditions and in reliance upon the
representations and warranties herein set forth, the Company hereby grants the Option to the Initial Purchasers to purchase, severally and not jointly, the Optional Notes at the same price as the Initial Purchasers shall pay for the Firm Notes and
the principal amount of the Optional Notes to be sold to each Initial Purchaser shall be that principal amount which bears the same ratio to the aggregate principal amount of Optional Notes being purchased as the principal amount of Firm Notes set
forth opposite the name of such Initial Purchaser in Schedule 1 hereto (or such number increased as set forth in Section 8). The Option may be exercised only to cover over-allotments in the sale of the Firm Notes by the Initial Purchasers.
The Option may be exercised once in whole or in part at any time not more than 30 days subsequent to the date of this Agreement upon notice in writing or by facsimile by the Representatives to the Company setting forth the amount (which shall be an
integral multiple of $1,000) of Optional Notes as to which the Initial Purchasers are exercising the Option. 
  
 The date for the delivery of and payment for the Optional Notes, being herein referred to as an “Optional Delivery Date,” which may be the First
Delivery Date (the First Delivery Date and the Optional Delivery Date, if any, being sometimes referred to as a “Delivery Date”), shall be determined by the Representatives but shall not be later than five full business days after written
notice of election to purchase Optional Notes is given. Delivery of the Optional Notes shall be made to the Initial Purchasers against payment of the purchase price by the Initial Purchasers. Payment for the Optional Notes shall be effected either
by wire transfer of immediately available funds to an account with a bank in The City of New York, the account number and the ABA number for such bank to be provided by the Company to the Representatives at least two business days in advance of the
Optional Delivery Date, or by such other manner of payment as may be agreed by the Company and the Representatives. It is understood that each Initial Purchaser has authorized the Representatives, for its account, to accept delivery of, issue a
receipt for, and make payment of the purchase price for, the Optional Notes that it has agreed to purchase. Merrill Lynch, Pierce, Fenner & Smith Incorporated and Lehman Brothers Inc., individually and not as representatives of the Initial
Purchasers, may (but shall not be obligated to) make payment of the purchase price for the Optional Notes to be purchased by any Initial Purchaser whose funds have not been received by the Delivery Date but such payment shall not relieve such
Initial Purchaser from its obligations hereunder. 
  

 14 

 (c) The Company will deliver against payment of the purchase price the Notes initially sold to qualified
institutional buyers (“QIBs”), as defined in Rule 144A under the Securities Act (“Rule 144A”) in the form of one or more permanent global certificates (the “Global Notes”), registered in the name of Cede & Co., as
nominee for The Depository Trust Company (“DTC”). Beneficial interests in the Notes initially sold to QIBs will be shown on, and transfers thereof will be effected only through, records maintained in book-entry form by DTC and its
participants. 
  
 The Global Notes will be made available, at the
request of the Representatives, for checking at least 24 hours prior to such Delivery Date. The Certificated Notes will be made available, at the request of the Initial Purchasers, for checking at least 48 hours prior to such Delivery Date.

  
 (d) Time shall be of the essence, and delivery at the time and
place specified pursuant to this Agreement is a further condition of the obligations of the Initial Purchasers hereunder. 
  
 3. Further Agreements of the Company. The Company further agrees with each Initial Purchaser as follows: 
  
 (a) The Company will advise the Initial Purchasers promptly
of any proposal to amend or supplement the Offering Memorandum and not to effect any such amendment or supplement without the consent of the Representatives and/or Sidley Austin Brown & Wood LLP, counsel to the Initial Purchasers.
Neither the consent of the Representatives, nor the Representatives’ delivery of any such amendment or supplement, shall constitute a waiver of any of the conditions set forth in Section 5. The Company will immediately notify the
Representatives, and confirm such notice in writing, of (i) any filing made by the Company of information relating to the offering of the Notes by the Company with any securities exchange or any other regulatory body in the United States or any
other jurisdiction, and (ii) prior to the completion of the placement of the Notes by the Initial Purchasers as evidenced by a notice in writing from the Representatives to the Company, any material changes in or affecting the condition, financial
or otherwise, or the earnings, business affairs or business prospects of the Company which (x) make any statement in the Offering Memorandum false or misleading or (y) are not disclosed in the Offering Memorandum. In such event or if during such
time any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Offering Memorandum in order that the Offering Memorandum will not include an untrue statement of a material fact or omit to state a
material fact necessary in order to make the statements therein, in the light of the circumstances existing at the time it is delivered to a purchaser, not misleading, to promptly notify the Representatives and/or Sidley Austin Brown & Wood
LLP, counsel to the Initial Purchasers, and prepare, subject to the first sentence of this Section 3(a), such amendment or supplement as may be necessary to correct such untrue statement or omission. 
  

 15 

 (b) The Company will furnish to the Initial Purchasers and to Sidley Austin Brown &
Wood LLP, counsel to the Initial Purchasers, copies of the Preliminary Offering Memorandum and the Offering Memorandum (and all amendments and supplements thereto) in each case as soon as available and in such quantities as the
Initial Purchasers reasonably request for internal use and for distribution to prospective purchasers; and to furnish to the Representatives on the date hereof two copies of the Offering Memorandum signed by duly authorized officers of the Company,
one of which will include the independent auditors’ reports therein manually signed by such independent auditors. The Company will pay the expenses of printing and distributing to the Initial Purchasers all such documents. 
  
 (c) The Company will use its reasonable efforts to take such
action as the Initial Purchasers may reasonably request from time to time, to qualify the Notes and the Conversion Shares for offering and sale under the securities laws of such jurisdictions as the Initial Purchasers may request and to comply with
such laws so as to permit the continuance of sales and dealings therein in such jurisdictions in the United States for as long as may be necessary to complete the resale of the Notes; provided that in connection therewith, the Company shall
not be required to qualify as a foreign corporation or otherwise subject itself to taxation in any jurisdiction in which it is not otherwise so qualified or subject. 
  
 (d) The Company will apply the proceeds from the sale of the Notes as set forth under “Use of
Proceeds” in the Offering Memorandum. 
  
 (e) During a period of 90 days from the date of the Offering Memorandum (the “Lockup Period”), the Company will not, and will cause its directors and executive officers not to, without the prior written consent of the
Representatives, (i) directly or indirectly, offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option right or warrant to purchase or lend or otherwise transfer or
dispose of any Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (collectively, the “Restricted Securities”) or (except as contemplated by the Registration Rights Agreement) file any
registration statement under the Securities Act with respect to any Restricted Securities, or (ii) enter into any swap or any other agreement or any transaction (other than the Operative Documents) that transfers, in whole or in part, directly or
indirectly, the economic consequence of ownership of any Restricted Securities, whether any such swap or transaction described in clause (i) or (ii) above is to be settled by delivery of Restricted Securities, in cash or otherwise. The restrictions
of this Section 3(e) shall not apply to (u) the Notes offered by the Offering Memorandum, (v) the issuance of shares of Common Stock or options to purchase shares of Common Stock pursuant to the Company’s employee benefit plans in effect on the
date of this Agreement, (w) the issuance of shares of Common Stock upon exercise or conversion of the Notes or any security outstanding on the date of this Agreement, (x) the issuance of shares of Common Stock or preferred stock in connection with
private placements to strategic 
  

 16 

 partners or as consideration for the Company’s acquisition of other companies or businesses, so long
as the recipients of any such shares issued in such private placements deliver to the Representatives an agreement to the effect described in the preceding sentence prior to the issuance of such shares but without any of the exceptions described in
this sentence, (y) the filing of one or more registration statements in order to register the shares of Common Stock or preferred stock issued pursuant to clause (x) above, or (z) the filing of one or more registration statements by the Company in
order to register Restricted Stock for sale by the Company on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, provided that no Restricted Stock registered pursuant to such registration statements is sold during the
Lockup Period. The Company further agrees to cause each executive officer and director of the Company to furnish to the Representatives, prior to the First Delivery Date, a letter or letters, in form and substance satisfactory to counsel to the
Initial Purchasers, pursuant to which each such person shall agree not to enter into any transaction described in clause (i) or (ii) of the first sentence of this paragraph; provided, however, that such restrictions shall not apply to
(A) sales of Common Stock by the Company’s directors and executive officers pursuant to 10b5-1 plans covering the Company’s securities as in effect on the date of this Agreement (provided that such plans may be amended subsequent to the
date of this Agreement to increase the number of shares of Common Stock that may be sold under such plans so long as the increase in the number of shares of Common Stock that may be sold under all such plans by all of such executive officers or
directors of the Company does not exceed 500,000 shares of Common Stock in the aggregate), and (B) donations to charitable organizations consistent with past practices. 
  
 (f) The Company agrees that it will not, and will cause its Affiliates (as defined in Rule 501(b) of
Regulation D) not to, directly or indirectly, solicit any offer to buy, sell or make any offer or sale of, or otherwise negotiate in respect of, securities of the Company of any class if, as a result of the doctrine of “integration”
referred to in Rule 502 under the Securities Act, such offer or sale would render invalid (for the purpose of (i) the sale of the Notes by the Company to the Initial Purchasers, (ii) the resale of the Notes by the Initial Purchasers to subsequent
purchasers or (iii) the resale of the Notes or Conversion Shares by such subsequent purchasers to others) the exemption from the registration requirements of the Securities Act provided by Section 4(2) thereof or by Rule 144A thereunder or
otherwise. Notwithstanding the foregoing, no stockholder of the Company that does not control, is not controlled by or is not under common control with, an officer or director of the Company shall be deemed to be an Affiliate for purposes of this
paragraph. 
  
 (g) For so long as any of the
Notes are “restricted securities” within the meaning of Rule 144(a)(3) under the Securities Act, the Company will provide to any holder of the Notes or to any prospective purchaser of the Notes designated by any holder, upon request of
such holder or prospective purchaser, information required to be provided by Rule 144A(d)(4) of the Securities Act if, at the time of such request, the Company is not subject to the reporting requirements under Section 13(a) or 15(d) of the Exchange
Act. 
  

 17 

 (h) Until the expiration of two years after the original issuance of the Notes, the
Company will not, and will cause its Affiliates (as defined in Rule 501(b) of Regulation D) not to, resell any Notes or Conversion Shares which are “restricted securities” (as such term is defined under Rule 144(a)(3) under the Securities
Act), whether as beneficial owner or otherwise (except as agent acting as a securities broker on behalf of and for the account of customers in the ordinary course of business in unsolicited broker’s transactions). Notwithstanding the foregoing,
no stockholder of the Company that does not control, is not controlled by or is not under common control with, an officer or director of the Company shall be deemed to be an Affiliate for purposes of this paragraph. 
  
 (i) Each of the Notes will bear, to the extent applicable,
the legend contained in “Notice to Investors” in the Offering Memorandum for the time period and upon the other terms stated therein, except after the Notes are resold pursuant to a registration statement effective under the Securities
Act. 
  
 (j) The Company will take such steps as
shall be necessary to ensure that it shall not become an “investment company” within the meaning of such term under the Investment Company Act, and the rules and regulations of the Commission thereunder. 
  
 (k) None of the Company or any of its affiliates will take,
directly or indirectly, any action which is designed to stabilize or manipulate, or which constitutes or which might reasonably be expected to cause or result in stabilization or manipulation, of the price of any security of the Company in
connection with the offering of the Notes. 
  
 (l) The Company will execute and deliver the Registration Rights Agreement in form and substance satisfactory to the Initial Purchasers. 
  
 (m) The Company will use its best efforts to assist the Initial Purchasers in arranging to cause the Notes to be accepted to trade in the
PORTAL market (“PORTAL”) of the National Association of Securities Dealers, Inc. (“NASD”). 
  
 (n) The Company will use its best efforts to cause the Notes to be accepted for clearance and settlement through the facilities of DTC.

  
 (o) The Company will use its best efforts to
have the Conversion Shares approved by The Nasdaq National Market (“Nasdaq”) for inclusion prior to the effectiveness of the Registration Statement. 
  

(p) The Company acknowledges and agrees that (i) the purchase and sale of the Notes pursuant to this Agreement is an arm’s-length
commercial transaction between the Company, on the one hand, and the several Initial 
  

 18 

 Purchasers, on the other hand, (ii) in connection with the offering contemplated hereby and the process
leading to such transaction each Initial Purchaser is and has been acting solely as a principal and is not the agent or fiduciary of the Company, or its stockholders, creditors, employees or any other party, (iii) no Initial Purchaser has assumed or
will assume an advisory or fiduciary responsibility in favor of the Company with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Initial Purchaser has advised or is currently advising the
Company on other matters) and no Initial Purchaser has any obligation to the Company with respect to the offering contemplated hereby except the obligations expressly set forth in this Agreement, (iv) the Initial Purchasers and their respective
affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company, and (v) the Initial Purchasers have not provided any legal, accounting, regulatory or tax advice with respect to the offering
contemplated hereby and the Company has consulted its own legal, accounting, regulatory and tax advisors to the extent it deemed appropriate. 
  
 4. Expenses. The Company agrees to pay: 
  
 (a) the costs incident to the authorization, issuance, sale and delivery of the Notes, and any taxes payable in that connection;

  
 (b) the costs incident to the preparation,
printing and distribution of the Preliminary Offering Memorandum, the Offering Memorandum and any amendment or supplement to the Offering Memorandum, all as provided in this Agreement; 
  
 (c) the costs of producing and distributing the Operative Documents; 
  
 (d) the fees and expenses of Cooley Godward LLP and Ernst
& Young LLP; 
  
 (e) the costs of
distributing the terms of agreement relating to the organization of the underwriting syndicate and selling group to the members thereof by mail, telex or other means of communication; 
  
 (f) the fees and expenses of qualifying the Notes and the Conversion Shares under the securities laws of the
several jurisdictions as provided in Section 3(c); 
  
 (g) all costs and expenses incident to (i) the preparation of the “road show” presentation materials and (ii) the road show traveling expenses of the Company; 
  
 (h) the costs of preparing the Notes; 
  

 19 

 (i) all expenses and fees in connection with the application for inclusion of the Notes
in the PORTAL market and the inclusion of the Conversion Shares on Nasdaq; 
  
 (j) the fees and expenses (including fees and disbursements of counsel) of the Trustee, and the costs and charges of any registrar, transfer agent, paying agent or conversion agent; and 
  
 (k) all other costs and expenses incident to the performance
of the obligations of the Company under this Agreement; 
  
 provided that,
except as provided in this Section 4 and in Section 7, the Initial Purchasers shall pay their own costs and expenses, including the costs and expenses of their counsel and any transfer taxes on the Notes which they may sell. 
  
 5. Conditions of the Initial Purchasers’ Obligations. The several
obligations of the Initial Purchasers hereunder are subject to the accuracy, when made and on each Delivery Date, of the representations and warranties of the Company contained herein, to the performance by the Company of its obligations hereunder,
and to each of the following additional terms and conditions: 
  
 (a) No Initial Purchaser shall have discovered and disclosed to the Company prior to or on such Delivery Date that the Offering Memorandum or any amendment or supplement thereto contains any untrue statement of a fact
which, in the opinion of counsel to the Initial Purchasers, is material or omits to state any fact which is material and necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

  
 (b) All corporate proceedings and other legal
matters incident to the authorization, form and validity of the Operative Documents and the Offering Memorandum or any amendment or supplement thereto, and all other legal matters relating to the Operative Documents and the transactions contemplated
thereby shall be satisfactory in all material respects to counsel to the Initial Purchasers, and the Company shall have furnished to such counsel all documents and information that they may reasonably request to enable them to pass upon such
matters. 
  
 (c) Cooley Godward LLP shall have
furnished to the Initial Purchasers their written opinion, as counsel to the Company, addressed to the Initial Purchasers and dated such Delivery Date, in form and substance satisfactory to the Initial Purchasers, to the effect that: 
  
 (i) the Company has been duly incorporated and is a validly
existing corporation in good standing under the laws of the State of Delaware; 
  

 20 

 (ii) the Company has the requisite corporate power to own its property and assets and to
conduct its business as described in the Offering Memorandum; 
  
 (iii) the Company is qualified as a foreign corporation to do business and is in good standing in the State of California; 
  
 (iv) the authorized, issued and outstanding capital stock of the Company was as set forth in the Offering Memorandum under the caption
“Capitalization” as of the date stated therein. 
  
 (v) the Conversion Shares issuable on the date hereof have been duly authorized and reserved for issuance upon conversion of the Notes by all necessary corporate action and are free of preemptive rights arising under
or pursuant to the Delaware General Corporation Law, the Company’s certificate of incorporation or bylaws; the Conversion Shares issuable on the date hereof, when so issued and delivered upon such conversion in accordance with the terms of the
Indenture, will be duly authorized and validly issued, fully paid and nonassessable; 
  
 (vi) the statements in the Offering Memorandum under the captions “Description of the Notes” and “Description of Capital
Stock,” insofar as they purport to summarize the provisions of the Indenture, the Registration Rights Agreement, the Notes, and the Common Stock (including the Conversion Shares) fairly present the material terms of such agreements in all
material respects and include such information that would be called for with respect to such matters pursuant to the Act and the rules and the regulations thereunder in a Registration Statement on Form S-3 filed with the Commission; 
  
 (vii) there is no restriction upon the voting or transfer of
any shares of Common Stock pursuant to the Company’s certificate of incorporation or bylaws; 
  
 (viii) to the knowledge of such counsel and other than as set forth in the Offering Memorandum, there is no action, proceeding or
investigation pending or overtly threatened against the Company before any court or administrative agency that questions the validity of the Purchase Agreement or the Notes or that would materially and adversely affect the consummation of the
transactions contemplated by the Purchase Agreement or the performance by the Company of its obligations thereunder or might result in a Material Adverse Effect (other than with respect to the Company’s or any of its subsidiaries’ patent
applications currently pending before the U.S. Patent and Trademark Office or before any foreign governmental authority that administers the registration of patents, as to which we express no opinion); 
  

 21 

 (ix) the execution and delivery of this Agreement, the Indenture and the Registration
Rights Agreement and the issuance of the Notes and the Conversion Shares do not violate any provision of the certificate of incorporation or bylaws of the Company and, to the knowledge of such counsel, do not violate or contravene (a) any
governmental statute, rule or regulation applicable to the Company or any of its subsidiaries; (b) any order, writ, judgment, injunction, decree or award which has been entered against the Company or any of its subsidiaries; or (c) the terms of any
Material Contract (with or without the passage of time and/or notice); 
  
 (x) all consents, approvals, authorizations, or orders of, and filings, registrations, and qualifications with, any regulatory authority or governmental body in the United States required for the execution and
delivery of the Purchase Agreement, the Indenture and the Registration Rights Agreement by the Company and the issuance of the Notes and the Conversion Shares have been made or obtained, except (a) as may be required under state securities or
“Blue Sky” laws in connection with the distribution of the Notes and the Conversion Shares (as to which such counsel expresses no opinion), (b) as may be required by the rules and regulations of the NASD (as to which such counsel expresses
no opinion), (c) as may be required under rules and regulations of the Nasdaq Stock Market (as to which such counsel expresses no opinion) and (d) any registration or qualification that may be required in connection with the Registration Rights
Agreement; 
  
 (xi) no registration of the
offering of the Notes or the Conversion Shares (assuming conversion on the date hereof pursuant to the terms of the Notes) under the Securities Act, and no qualification of the Indenture under the Trust Indenture Act, is required in connection with
the purchase of the Notes by the Initial Purchasers or the initial resale of the Notes by the Initial Purchasers in the manner contemplated in the Purchase Agreement other than any registration or qualification that may be required in connection
with the Registration Rights Agreement; 
  
 (xii)
the statements in the Offering Memorandum under the caption “Certain United States Federal Income Tax Considerations,” insofar as they purport to constitute summaries of matters of United States federal income tax law and regulations or
legal conclusions with respect thereto, constitute accurate summaries of the matters described therein in all material respects; 
  
 (xiii) the Company is not and will not become, as a result of the consummation of the transactions contemplated by the Purchase Agreement,
and application of the net proceeds therefrom as described in the Offering Memorandum, required to register as an “investment company,” within the meaning of the Investment Company Act of 1940, as amended; 
  

 22 

 (xiv) the Company has all necessary corporate right, power and authority to execute and
deliver each of the Operative Documents to which it is a party and to perform its obligations thereunder and to issue, sell and deliver the Notes to the Initial Purchasers; 
  
 (xv) this Agreement has been duly authorized, executed and delivered by the Company; 
  
 (xvi) the Indenture has been duly authorized, executed and
delivered by the Company and constitutes valid and binding obligations of the Company enforceable against the Company in accordance with its terms, except as the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer,
reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally, by general principles of equity and limitations on availability of equitable relief, including specific performance (regardless of whether
such enforceability is considered in a proceeding in equity or at law); 
  
 (xvii) the Registration Rights Agreement has been duly authorized, executed and delivered by the Company and constitutes valid and binding obligations of the Company enforceable against the Company in accordance with
its terms, except as rights to indemnity contained therein may be limited by applicable law and except as the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and other similar laws
relating to or affecting creditors’ rights generally, by general principles of equity and limitations on availability of equitable relief, including specific performance (regardless of whether such enforceability is considered in a proceeding
in equity or at law); and 
  
 (xviii) the Notes
have been duly authorized by the Company and when executed, issued and authenticated in accordance with terms of the Indenture and delivered to and paid for by the Initial Purchasers, will constitute legally valid and binding obligations of the
Company, entitled to the benefits of the Indenture and enforceable against the Company in accordance with their terms, except as the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and
other similar laws relating to or affecting creditors’ rights generally, by general principles of equity and limitations on availability of equitable relief, including specific performance (regardless of whether such enforceability is
considered in a proceeding in equity or at law). 
  
 In rendering
such opinion, such counsel may state that its opinion is limited to matters governed by the federal laws of the United States of America, the laws of the State of California and the Delaware General Corporation Law, and with respect to the
enforceability and binding effect of the Indenture, the Registration Rights Agreement and the Notes, solely the laws of the state of New York, and in respect of matters of fact, 
  

 23 

 upon certificates of officers of the Company, provided that such counsel shall state that it believes that the Initial
Purchasers and it are justified in relying upon such certificates. Such counsel shall also have furnished to the Initial Purchasers a written statement, addressed to the Initial Purchasers and dated such Delivery Date, in form and substance
satisfactory to the Initial Purchasers, to the effect that during the course of preparing the Offering Memorandum, such counsel participated in conferences with officers and other representatives of the Company, the Company’s independent
registered public accounting firm, the Initial Purchasers and their counsel, at which the contents of the Offering Memorandum were discussed, and while such counsel has not independently verified and is not passing upon or assuming responsibility
for the accuracy, completeness or fairness of the statements made in the Offering Memorandum except as explicitly set forth above, nothing has come to the attention of such counsel that causes it to believe that the Offering Memorandum (other than
the financial statements, financial and statistical data and supporting schedules as to which such counsel shall make no statement), as of its date or as of such Delivery Date, contained or contains any untrue statement of a material fact or omitted
or omits to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. 
  

(d) Bradley Arant Rose & White LLP shall have furnished to the Initial Purchasers their written opinion, as special
Alabama counsel to the Company, addressed to the Initial Purchasers and dated such Delivery Date, in form and substance satisfactory to the Initial Purchasers, to the effect that: 
  
 (i) Nektar Alabama has been duly incorporated and is validly existing as a corporation in good standing
under the laws of the State of Alabama and has all corporate power and authority necessary to own or hold its properties and conduct the businesses in which it is engaged, as described in the Offering Memorandum; except as otherwise disclosed in the
Offering Memorandum, all of the issued and outstanding capital stock of Nektar Alabama has been duly authorized and validly issued, is fully paid and non-assessable and, based on the stock ledger of Nektar Alabama, is owned by the Company, directly
or through subsidiaries; and to the knowledge of such counsel, none of the outstanding shares of capital stock of Nektar Alabama was issued in violation of the preemptive or similar rights of any securityholder of Nektar Alabama; and 
  
 (ii) the execution, delivery and performance of this
Agreement, the Indenture and the Registration Rights Agreement and the issuance of the Notes and the Conversion Shares and the consummation of the transactions contemplated hereby and thereby by the Company do not result in any violation of the
provisions of the articles of incorporation or bylaws of Nektar Alabama. 
  
 In rendering such opinion, such counsel may state that its opinion is limited to matters governed by the laws of the State of Alabama. 
  

 24 

 (e) Sidley Austin Brown & Wood LLP, shall have furnished to the
Initial Purchasers their written opinion, as counsel to the Initial Purchasers, addressed to the Initial Purchasers and dated such Delivery Date, in form and substance satisfactory to the Initial Purchasers. 
  
 (f) With respect to the letter of Ernst & Young LLP
delivered to the Initial Purchasers concurrently with the execution of this Agreement (the “initial letter”), the Company shall have furnished to the Initial Purchasers a letter (the “bring-down letter”) of such accountants,
addressed to the Initial Purchasers and dated such Delivery Date (i) confirming that they are independent accountants within the meaning of the Securities Act and are in compliance with the applicable requirements relating to the qualification of
accountants under Rule 2-01 of Regulation S-X of the Commission, (ii) stating, as of the date of the bring-down letter (or, with respect to matters involving changes or developments since the respective dates as of which specified financial
information is given in the Offering Memorandum, as of a date not more than five days prior to the date of the bring-down letter), the conclusions and findings of such firm with respect to the financial information and other matters covered by the
initial letter and (iii) confirming in all material respects the conclusions and findings set forth in the initial letter. 
  
 (g) The Company shall have furnished to the Initial Purchasers on such Delivery Date a certificate, dated such Delivery Date and delivered
on behalf of the Company by its chief executive officer and its chief financial officer, in form and substance satisfactory to the Initial Purchasers, to the effect that: 
  
 (i) the representations, warranties and agreements of the Company in Section 1 hereof are true and correct
as of the date given and as of such Delivery Date; and the Company has complied in all material respects with all its agreements contained herein to be performed prior to or on such Delivery Date; 
  
 (ii) (A) neither the Company nor any of its subsidiaries has
sustained, since the date of the latest audited financial statements included in the Offering Memorandum, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any
labor dispute or court or governmental action, order or decree, except (x) as set forth or contemplated in the Offering Memorandum and (y) for operating losses incurred in the ordinary course of business, or (B) since such date there has not been
any change in the capital stock or long-term debt of the Company or any of its subsidiaries (except as disclosed in the Offering Memorandum and except for exercise of outstanding options described in the Offering Memorandum or pursuant to Authorized
Grants and as provided in Section 1(l) above), or any change, or any development involving a prospective change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company
and its subsidiaries considered as one enterprise, except as set forth or contemplated in the Offering Memorandum; and 
  

 25 

 (iii) Such officer has carefully examined the Offering Memorandum and, in such
officer’s opinion (A) the Offering Memorandum, as of its date, did not include any untrue statement of a material fact and did not omit to state any material fact necessary to make the statements therein, in the light of the circumstances under
which they were made, not misleading, and (B) since the date of the Offering Memorandum, no event has occurred which should have been set forth in a supplement or amendment to the Offering Memorandum. 
  
 (h) The Indenture shall have been duly executed and
delivered by the Company and the Trustee and the Notes shall have been duly executed and delivered by the Company and duly authenticated by the Trustee. 
  
 (i) The Company and the Representatives shall have executed and delivered the Registration Rights Agreement (in form and substance
satisfactory to the Initial Purchasers) and the Registration Rights Agreement shall be in full force and effect. 
  
 (j) The NASD shall have accepted the Notes for trading on PORTAL. 
  
 (k) (i) Neither the Company nor any of its subsidiaries shall have sustained, since the date of the latest
audited financial statements included in the Offering Memorandum, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental
action, order or decree, except (A) as set forth or contemplated in the Offering Memorandum and (B) for operating losses incurred in the ordinary course of business, and (ii) since such date there shall not have been any change in the capital stock
or long-term debt of the Company or any of its subsidiaries (except as disclosed in the Offering Memorandum and except for exercise of outstanding options described in the Offering Memorandum or pursuant to Authorized Grants and as provided in
Section 1(m) above), or any change, or any development involving a prospective change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries
considered as one enterprise, except as set forth or contemplated in the Offering Memorandum, the effect of which, in any such case described in clause (i) or (ii), is, in the reasonable judgment of the Initial Purchasers, so material and adverse as
to make it impracticable or inadvisable to proceed with the sale or the delivery of the Notes being delivered on such Delivery Date on the terms and in the manner contemplated in the Offering Memorandum. 
  
 (l) The Company shall have furnished to the Initial
Purchasers such further information, certificates and documents as the Initial Purchasers may reasonably request to evidence compliance with the conditions set forth in this Section 5. 
  

 26 

 All opinions, letters, evidence and certificates mentioned above or elsewhere in this Agreement shall be
deemed to be in compliance with the provisions hereof only if they are in form and substance satisfactory to counsel to the Initial Purchasers. 
  
 If any condition specified in this Section 5 shall not have been fulfilled when and as required to be fulfilled, this Agreement may be terminated by the
Representatives by notice to the Company at any time at or prior to the First Delivery Date, and such termination shall be without liability of any party to any other party except as provided in Section 4 and except that Sections 1 and 7 shall
survive any such termination and remain in full force and effect. 
  
 6. Representations, Warranties and Agreements of Initial Purchasers. Each Initial Purchaser, severally and not jointly, represents and warrants that such Initial Purchaser is a QIB. Each Initial Purchaser, severally and not jointly,
agrees with the Company that: 
  
 (a) The Notes
and the Conversion Shares have not been and will not be registered under the Securities Act in connection with the initial offering of the Notes. 
  
 (b) Such Initial Purchaser is a QIB; 
  
 (c) Such Initial Purchaser will not offer or sell the Notes in the United States by means of any form of general solicitation or general
advertising within the meaning of Rule 502(c) of Regulation D, including (i) any advertisement, article, notice or other communication published in any newspaper, magazine or similar medium or broadcast over television or radio, or (ii) any seminar
or meeting whose attendees have been invited by any general solicitation or general advertising in the United States; and 
  
 (d) Such Initial Purchaser has not offered or sold, and will not offer or sell, any Notes in the United States except to persons whom it
reasonably believes to be QIBs. 
  
 7. Indemnification and
Contribution. 
  
 (a) The Company shall indemnify and hold
harmless each Initial Purchaser, its officers and employees and each person, if any, who controls any Initial Purchaser within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any loss, claim, damage
or liability, joint or several, or any action in respect thereof (including, but not limited to, any loss, claim, damage, liability or action relating to purchases and sales of the Notes), to which that Initial Purchaser, officer, employee or
controlling person may become subject: 
  

 27 

 (i) insofar as such loss, claim, damage, liability or action arises out of, or is based
upon: (A) any untrue statement or alleged untrue statement of a material fact contained in (1) any Preliminary Offering Memorandum or the Offering Memorandum, or in any amendment or supplement thereto, or (2) any blue sky application or other
document prepared or executed by the Company (or based upon any written information furnished by the Company) filed in any jurisdiction specifically for the purpose of qualifying any or all of the Notes under the securities laws of any state or
other jurisdiction (such application, document or information being hereinafter called a “Blue Sky Application”), or (B) the omission or alleged omission to state therein any material fact necessary to make the statements therein not
misleading; or 
  
 (ii) to the extent of the
aggregate amount paid in settlement of any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or of any claim whatsoever based upon any such untrue statement or omission, or any such alleged
untrue statement or omission; provided that (subject to Section 7(c)) any such settlement is effected with the written consent of the Company, which consent will not be unreasonably withheld, 
  
 and shall reimburse each Initial Purchaser and each such officer, employee and controlling
person promptly upon demand for any and all expense whatsoever, as incurred (including the fees and disbursements of counsel chosen by the Representatives, except as reimbursement of such fees may be limited by Section 7(c)), reasonably incurred by
that Initial Purchaser, officer, employee or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred; provided,
however, that the Company shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of, or is based upon, any untrue statement or alleged untrue statement or omission or alleged
omission made in any Preliminary Offering Memorandum or the Offering Memorandum, or in any such amendment or supplement, or in any Blue Sky Application in reliance upon and in conformity with the written information furnished to the Company by or on
behalf of any Initial Purchaser specifically for inclusion therein and described in Section 7(e); provided, further, that as to any Preliminary Offering Memorandum, this indemnity agreement shall not inure to the benefit of any Initial
Purchaser, its officers or employees or any person controlling that Initial Purchaser on account of any loss, claim, damage, liability or action arising from the sale of Notes to any person by that Initial Purchaser if that Initial Purchaser failed
to send or give a copy of the Offering Memorandum, as the same may be amended or supplemented, to that person, and the untrue statement or alleged untrue statement of a material fact or omission or alleged omission to state a material fact in such
Preliminary Offering Memorandum was corrected in the Offering Memorandum, unless such failure resulted from non-compliance by the Company with Section 3(b). The foregoing indemnity agreement is in addition to any liability which the Company may
otherwise have to any Initial Purchaser or to any officer, employee or controlling person of that Initial Purchaser. 
  

 28 

 (b) Each Initial Purchaser, severally and not jointly, shall indemnify and hold harmless, the Company,
its officers and directors, and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any loss, claim, damage or liability, joint or several, or any
action in respect thereof, to which the Company or any such director, officer or controlling person may become subject, insofar as such loss, claim, damage, liability or action arises out of, or is based upon: 
  
 (i) any untrue statement or alleged untrue statement of a
material fact contained in any Preliminary Offering Memorandum or the Offering Memorandum or in any amendment or supplement thereto, or in any Blue Sky Application, or 
  
 (ii) the omission or alleged omission to state therein any material fact necessary to make the statements
therein not misleading, 
  
 but in each case only to the extent that such untrue
statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with the written information furnished to the Company by or on behalf of that Initial Purchaser specifically for inclusion therein and
described in Section 7(e), and shall reimburse the Company and any such director, officer or controlling person promptly upon demand for any legal or other expenses (except as reimbursement may be limited by Section 7(c)) reasonably incurred by the
Company or any such director, officer or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred. The foregoing indemnity
agreement is in addition to any liability which any Initial Purchaser may otherwise have to the Company or any such director, officer or controlling person. 
  
 (c) Promptly after receipt by an indemnified party under this Section 7 of notice of any claim or the commencement of any action, the indemnified party
shall, if a claim in respect thereof is to be made against the indemnifying party under this Section 7, notify the indemnifying party in writing of the claim or the commencement of that action; provided, however, that the failure to
notify the indemnifying party shall not relieve it from any liability which it may have under this Section 7 except to the extent it has been materially prejudiced by such failure and, provided, further, that the failure to notify the
indemnifying party shall not relieve it from any liability which it may have to an indemnified party otherwise than under Section 7(a) and 7(b). If any such claim or action shall be brought against an indemnified party, and it shall notify the
indemnifying party thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it wishes, jointly with any other similarly notified indemnifying party, to assume the defense thereof with counsel satisfactory to
the indemnified party. After notice from the indemnifying party to the indemnified party of its election to assume the defense of such claim or action, the indemnifying party shall not be liable to the indemnified party under this Section 7 for any
legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however, that the Initial Purchasers shall have the right to employ
counsel to represent jointly the Initial Purchasers and their respective officers, employees and 
  

 29 

 controlling persons who may be subject to liability arising out of any claim in respect of which indemnity may be sought
by the Initial Purchasers against the Company under this Section 7, if the Initial Purchasers shall have reasonably concluded that there may be one or more legal defenses available to the Initial Purchasers and their respective officers, employees
and controlling persons that are different from or additional to those available to the Company and its officers, employees and controlling persons, the fees and expenses of a single separate counsel, in addition to local counsel, shall be paid by
the Company. No indemnifying party shall: 
  
 (i)
without the prior written consent of the indemnified parties (which consent shall not be unreasonably withheld) settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding
in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent (1) includes an unconditional
release of each indemnified party from all liability arising out of such claim, action, suit or proceeding and (2) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party,
or 
  
 (ii) be liable for any settlement of any
such action effected without its written consent (which consent shall not be unreasonably withheld) but if settled with its written consent or if there be a final judgment of the plaintiff in any such action, the indemnifying party agrees to
indemnify and hold harmless any indemnified party from and against any loss of liability by reason of such settlement or judgment. 
  
 (d) If the indemnification provided for in this Section 7 shall for any reason be unavailable or insufficient to hold harmless an indemnified party under
Section 7(a) or 7(b) in respect of any loss, claim, damage or liability, or any action in respect thereof, referred to therein, each indemnifying party shall, in lieu of indemnifying such indemnified party, contribute to the amount paid or payable
by such indemnified party as a result of such loss, claim, damage or liability, or action in respect thereof: 
  
 (i) in such proportion as shall be appropriate to reflect the relative benefits received by the Company on the one hand and the Initial
Purchasers on the other from the offering of the Notes, or 
  
 (ii) if the allocation provided by clause 7(d)(i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause 7(d)(i) but also the relative
fault of the Company on the one hand and the Initial Purchasers on the other with respect to the statements or omissions or alleged statements or alleged omissions that resulted in such loss, claim, damage or liability (or action in respect
thereof), as well as any other relevant equitable considerations. 
  

 30 

 The relative benefits received by the Company on the one hand and the Initial Purchasers on the other
with respect to such offering shall be deemed to be in the same proportion as the total net proceeds from the offering of the Notes purchased under this Agreement (before deducting expenses) received by the Company on the one hand, and the total
discounts and commissions received by the Initial Purchasers with respect to the Notes purchased under this Agreement, on the other hand, bear to the total gross proceeds from the offering of the Notes under this Agreement, in each case as set forth
in the table under the caption “Plan of Distribution” in the Offering Memorandum. 
  
 The relative fault shall be determined by reference to whether the untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the
Company or the Initial Purchasers, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such statement or omission. 
  
 The Company and the Initial Purchasers agree that it would not be just and equitable if the amount of contributions pursuant
to this Section 7(d) were to be determined by pro rata allocation (even if the Initial Purchasers were treated as one entity for such purpose) or by any other method of allocation which does not take into account the equitable considerations
referred to herein. The amount paid or payable by an indemnified party as a result of the loss, claim, damage or liability, or action in respect thereof, referred to above in this Section 7(d) shall be deemed to include, for purposes of this Section
7(d), any legal or other expenses reasonably incurred by such indemnified party in connection with investigating, preparing or defending any such litigation, investigation or proceeding by any governmental agency or body, or commenced or threatened
action or claim. 
  
 Notwithstanding the provisions of this
Section 7(d), no Initial Purchaser shall be required to contribute any amount in excess of the amount by which the total price at which the Notes resold by it in the initial placement of such Notes were offered to investors exceeds the amount of any
damages which such Initial Purchaser 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. 
  
 For purposes of this Section 7(d), each person, if any, who controls an Initial Purchaser within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act shall have the same rights to contribution as such Initial
Purchaser, and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act shall have the same rights to contribution as the Company. The Initial Purchasers’ obligations
to contribute as provided in this Section 7(d) are several in proportion to their respective purchase obligations and not joint. 
  

 31 

 (e) The Initial Purchasers severally confirm that the statements (i) with respect to the offering of the
Notes set forth in the third sentence of the ninth paragraph on the cover page of the Offering Memorandum; (ii) in the third and fifth paragraphs under the heading “Plan of Distribution”; (iii) in the paragraph under the heading “Plan
of Distribution—Notes Are Not Being Registered” in the Offering Memorandum; (v) in the third and fourth sentences of the first paragraph under the heading “Plan of Distribution—New Issue of Notes” in the Offering Memorandum;
and (vi) in the first and third sentences of the first paragraph under the heading “Plan of Distribution—Price Stabilization and Short Positions” in the Offering Memorandum are correct and constitute the only information furnished in
writing to the Company by or on behalf of the Initial Purchasers specifically for inclusion in the Offering Memorandum. 
  
 8. Defaulting Initial Purchasers. 
  
 If, on any Delivery Date, any Initial Purchaser defaults in the performance of its obligations under this Agreement, the remaining non-defaulting Initial
Purchasers shall be obligated to purchase the aggregate principal amount of Notes which the defaulting Initial Purchaser agreed but failed to purchase on such Delivery Date in the respective proportions which the total aggregate principal amount of
Notes set opposite the name of each remaining non-defaulting Initial Purchaser in Schedule 1 hereto bears to the total aggregate principal amount of Notes set opposite the names of all the remaining non-defaulting Initial Purchasers in Schedule 1
hereto; provided, however, that the remaining non-defaulting Initial Purchasers shall not be obligated to purchase any Notes on such Delivery Date if the total aggregate principal amount of Notes which the defaulting Initial Purchasers
agreed but failed to purchase on such date exceeds 9.09% of the total aggregate principal amount at maturity of Notes to be purchased on such Delivery Date, and any remaining non-defaulting Initial Purchaser shall not be obligated to purchase more
than 110% of the aggregate principal amount at maturity of Notes which it agreed to purchase on such Delivery Date pursuant to the terms of Section 2. If the foregoing maximums are exceeded, the remaining non-defaulting Initial Purchasers, or those
other purchasers satisfactory to the Initial Purchasers who so agree, shall have the right, but shall not be obligated, to purchase on such Delivery Date, in such proportion as may be agreed upon among them, the total aggregate principal amount of
Notes to be purchased on such Delivery Date. If the remaining Initial Purchasers or other purchasers satisfactory to the Initial Purchasers do not elect to purchase on such Delivery Date the aggregate principal amount of Notes which the defaulting
Initial Purchasers agreed but failed to purchase, this Agreement (or with respect to the Optional Delivery Date, the obligation of the Initial Purchasers to purchase the Optional Notes) shall terminate without liability on the part of any
non-defaulting Initial Purchasers and the Company, except that the Company will continue to be liable for the payment of expenses to the extent set forth in Sections 4 and 10. As used in this Agreement, the term “Initial Purchaser”
includes, for all purposes of this Agreement unless the context requires otherwise, any party not listed in Schedule 1 hereto who, pursuant to this Section 8, purchases Notes which a defaulting Initial Purchaser agreed but failed to purchase.

  
 Nothing contained herein shall relieve a defaulting Initial
Purchaser of any liability it may have to the Company for damages caused by its default. If other 
  

 32 

 purchasers are obligated or agree to purchase the Notes of a defaulting or withdrawing Initial Purchaser, either the
remaining non-defaulting Initial Purchasers or the Company may postpone the Delivery Date for up to seven full business days in order to effect any changes in the Offering Memorandum or in any other document or arrangement that, in the opinion of
counsel to the Company or counsel to the Initial Purchasers, may be necessary. 
  
 9. Termination. 
  
 (a)
The obligations of the Initial Purchasers hereunder may be terminated by the Initial Purchasers by notice given to and received by the Company prior to delivery of and payment for the Notes if, prior to that time: (i) there has occurred one of the
events described in Section 5(k), or (ii) there has occurred any material adverse change in the financial markets in the United States, any outbreak of hostilities or escalation thereof or other calamity or crisis or any change or development
involving a prospective change in national or international political, financial or economic conditions, in each case the effect of which is such as to make it, in the judgment of the Representatives, impracticable or inadvisable to market the Notes
or to enforce contracts for the sale of the Notes, or (iii) trading in any securities of the Company has been suspended or materially limited by the Commission or The Nasdaq National Market, or if trading generally on the American Stock Exchange or
the New York Stock Exchange or in The Nasdaq National Market has been suspended or materially limited, or minimum or maximum prices for trading have been fixed, or maximum ranges for prices have been required, by any of said exchanges or by such
system or by order of the Commission, the National Association of Securities Dealers, Inc. or any other governmental authority, or a material disruption has occurred in commercial banking or securities settlement or clearance services in the United
States or (iv) a banking moratorium has been declared by either Federal or New York authorities. 
  
 (b) If this Agreement is terminated pursuant to this Section 9, such termination shall be without liability of any party to any other party except as
provided in Section 10 and provided, further, that Sections 1, 7 and 13 shall survive such termination and remain in full force and effect. 
  
 10. Reimbursement of Initial Purchasers’ Expenses. If (a) the Company shall fail to tender the Notes for delivery to the Initial Purchasers
for any reason permitted under this Agreement or (b) the Initial Purchasers shall decline to purchase the Notes for any reason permitted under this Agreement (including the termination of this Agreement pursuant to Section 9), the Company shall
reimburse the Initial Purchasers for the fees and expenses of their counsel and for such other out-of-pocket expenses as shall have been incurred by them in connection with this Agreement and the proposed purchase of the Notes, and upon demand the
Company shall pay the full amount thereof to the Initial Purchasers. If this Agreement is terminated pursuant to Section 8 by reason of the default of one or more Initial Purchasers, the Company shall not be obligated to reimburse any defaulting
Initial Purchaser on account of those expenses. 
  

 33 

 11. Notices, etc. All statements, requests, notices and agreements hereunder shall be in writing,
and: 
  
 (a) if to the Initial Purchasers, shall
be delivered or sent by mail, telex or facsimile transmission to Merrill Lynch & Co., North Tower, World Financial Center, New York, New York 10281, Attention: Paul A. Pepe (Fax: 212-738-1069) and to Lehman Brothers Inc., 745 Seventh Avenue, New
York, New York 10019, Attention: Syndicate Department (Fax: 646-834-8133) and 399 Park Avenue, 10th Floor, New York,
New York 10022, Attention: Director of Litigation, Official General Counsel (Fax: 212-520-0421); and 
  
 (b) if to the Company, shall be delivered or sent by mail, telex or facsimile transmission to Nektar Therapeutics, 150 Industrial Road,
San Carlos, California 94070, Attention: Secretary (Fax: 650-620-5360). 
  
 provided, however, that any notice to an Initial Purchaser pursuant to Section 7(c) shall be delivered or sent by mail, telex or facsimile transmission to each such Initial Purchaser, which address will be supplied to any
other party hereto by Merrill Lynch upon request. Any such statements, requests, notices or agreements shall take effect at the time of receipt thereof. The Company shall be entitled to act and rely upon any request, consent, notice or agreement
given or made on behalf of the Initial Purchasers by Merrill Lynch. 
  
 12. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the Initial Purchasers, the Company and their respective successors. This Agreement and the terms and provisions hereof
are for the sole benefit of only those persons, except that the representations, warranties, indemnities and agreements of the Company contained in this Agreement shall also be deemed to be for the benefit of the officers and employees of each
Initial Purchaser and the person or persons, if any, who control each Initial Purchaser within the meaning of Section 15 of the Securities Act and any indemnity agreement of the Initial Purchasers contained in Section 7(b) of this Agreement shall be
deemed to be for the benefit of directors, officers and employees of the Company, and any person controlling the Company within the meaning of Section 15 of the Securities Act. Nothing contained in this Agreement is intended or shall be construed to
give any person, other than the persons referred to in this Section 12, any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein. 
  
 13. Survival. The respective indemnities, representations, warranties
and agreements of the Company and the Initial Purchasers contained in this Agreement or made by or on behalf of them, respectively, pursuant to this Agreement, shall survive the delivery of and payment for the Notes and shall remain in full force
and effect, regardless of any termination or cancellation of this Agreement or any investigation made by or on behalf of any of them or any person controlling any of them. 
  
 14. Definition of the Terms “Business Day” and “Subsidiary.” For purposes of this Agreement, (a)
”business day” means any day on which the New York Stock Exchange, Inc. is open for trading and (b) ”subsidiary” has the meaning set forth in Rule 405 of the rules and regulations promulgated under the Securities Act. 

 

 34 

 15. Governing Law. This Agreement shall be governed by, and construed in accordance with, the laws
of the State of New York. 
  
 16. Counterparts. This
Agreement may be executed in one or more counterparts and, if executed in more than one counterpart, the executed counterparts shall each be deemed to be an original but all such counterparts shall together constitute one and the same instrument.

  
 17. Headings. The headings herein are inserted for
convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement. 
  

 35 

 If the foregoing correctly sets forth the agreement between the Company and the Initial Purchasers,
please indicate your acceptance in the space provided for that purpose below. 
  

			
	Very truly yours,
	
	 NEKTAR THERAPEUTICS

		
	 By:
	 	 /s/ Ajit Gill

	 Name:
	 	Ajit Gill
	 Title:
	 	Chief Executive Officer

  
 Accepted and agreed by:

  
 MERRILL LYNCH, PIERCE, FENNER & SMITH 
 INCORPORATED 
  

			
	 By:
	 	 /s/    Saira Ramasastry

	 	 	        Authorized Representative

  
 LEHMAN BROTHERS INC. 
  

			
	By:	 	 /s/    David A. Galper

	 Name:
	 	David A. Galper
	 Title:
	 	Vice President

  
 For themselves and as Representatives
of the 
 other Initial Purchasers named in Schedule I hereto. 
  

 36 

 SCHEDULE 1 
  

				
	 Initial Purchasers    

	  	Principal Amount
of Firm Notes

	 Merrill Lynch, Pierce, Fenner & Smith Incorporated
	  	$	96,251,000
	 Lehman Brothers Inc.
	  	 	96,251,000
	 Goldman, Sachs & Co.
	  	 	26,675,000
	 Deutsche Bank Securities Inc.
	  	 	20,075,000
	 WR Hambrecht + Co, LLC.
	  	 	8,937,500
	 Leerink Swann & Company.
	  	 	8,937,000
	 SG Cowen & Co., LLC.
	  	 	8,937,000
	 SunTrust Capital Markets, Inc.
	  	 	8,937,000
	 	  	
	

	 Total
	  	$	275,000,000

  

 37

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00091-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00091-of-00352.parquet"}]]