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Aptevo Therapeutics Inc.

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See the reverse side of this notice to obtainproxy materials and voting instructions.*** Exercise Your Right to Vote ***Important Notice Regarding the Availability of Proxy Materials for theStockholder Meeting to Be Held on <mtgdate>.You are receiving this communication because you holdshares in the above named company.This is not a ballot. You cannot use this notice to votethese shares. This communication presents only anoverview of the more complete proxy materials that areavailable to you on the Internet. You may view the proxymaterials online at www.proxyvote.com or easily request apaper copy (see reverse side).We encourage you to access and review all of the importantinformation contained in the proxy materials before voting.Meeting InformationMeeting Type:<mtgtype>For holders as of:<recdate>Date: Time: <mtgtime>Location:0000377870_1 R1.0.1.17APTEVO THERAPEUTICS INC.APTEVO THERAPEUTICS INC.C/O BROADRIDGEP.O. BOX 1342BRENTWOOD, NY 11717Annual MeetingApril 02, 2018June 01, 2018June 01, 20189:00 AM PDTWorld Trade Center Seattle2200 Alaskan WaySeattle, WA 98121

Before You Vote How to Access the Proxy Materials Proxy Materials Available to VIEW or RECEIVE:How to View Online:Have the information that is printed in the box marked by the arrow (located on thefollowing page) and visit: www.proxyvote.com.How to Request and Receive a PAPER or E-MAIL Copy:If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request:1)BY INTERNET:www.proxyvote.com2)BY TELEPHONE:1-800-579-16393)BY E-MAIL*:sendmaterial@proxyvote.com*If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line...........0000377870_2 R1.0.1.171. Annual Report 2. Notice & Proxy Statement Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 20, 2018 to facilitate timely delivery.

Voting items0000377870_3 R1.0.1.17The Board of Directors recommends you vote FOR the following:1. To elect two nominees to the Board of Directors to hold office for a term expiring at our 2021 Annual Meeting of Stockholders. Nominees01 Daniel J. Abdun-Nabi02 Grady Grant, III2. To approve the Company's 2018 Stock Incentive Plan.3. To ratify the selection by the Audit Committee of the Board of Directors of Ernst & Young LLP as the independent registered public accounting firm of the company for the fiscal year ending December 31, 2018.NOTE: Such other business as may properly come before the meeting or any adjournment thereof.

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