UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

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Nektar Therapeutics

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Your Vote Counts!NEKTAR THERAPEUTICS2022 Annual MeetingVote by June 7, 2022 11:59 PM Eastern TimeNEKTAR THERAPEUTICS ATTN: SECRETARY455 MISSION BAY BOULEVARD SOUTH SAN FRANCISCO, CA 94158D84477-P69224You invested in NEKTAR THERAPEUTICS and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the stockholder meeting to be held on June 8, 2022.Get informed before you vote View the Notice and Proxy Statement and Form 10-K Wrap online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 25, 2022. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. For complete information and to vote, visit www.ProxyVote.com Control #Smartphone users Vote Virtually at the Meeting*Point your camera here and June 8, 2022 2:00 PM Pacific Time vote without entering a control number Virtually at: www.virtualshareholdermeeting.com/NKTR2022*Please check the meeting materials for any special requirements for meeting attendance.

Vote at www.ProxyVote.comTHIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items Board Recommends1. Election of DirectorsNominees:1a. Diana M. Brainard For 1b. R. Scott Greer For2. To approve an amendment to our Amended and Restated 2017 Performance Incentive Plan to increase the aggregate number of shares of common stock authorized for issuance under the plan by 5,000,000 shares. For3. To ratify the selection of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022. For4. To approve a non-binding advisory resolution regarding our executive compensation (a “say-on-pay” vote). For Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Sign up for E-delivery”.D84478-P69224