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FRANKLIN STREET PROPERTIES CORP.

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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on May 10, 2018. FRANKLIN STREET PROPERTIES CORP. You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of FRANKLIN STREET PROPERTIES CORP. 401 EDGEWATER PLACE SUITE 200 WAKEFIELD, MA 01880 the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy materials and voting instructions. E38133-P01836 See the reverse side of this notice to obtain Meeting Information Meeting Type:Annual Meeting For holders as of:March 2, 2018 Date: May 10, 2018Time: 11:00 a.m., Eastern Time Location: Four Points by Sheraton Wakefield Boston Hotel & Conference Center One Audubon Road Wakefield, MA 01880 LOGO

Before You Vote How to Access the Proxy Materials Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the by the arrow XXXX XXXX XXXX XXXX (located on the following page) in the subject line. How To Vote Please Choose One of the Following Voting Methods marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions. E38134-P01836 Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. Proxy Materials Available to VIEW or RECEIVE: NOTICE AND PROXY STATEMENT2017 ANNUAL REPORT TO STOCKHOLDERS How to View Online: following 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.com 2) BY TELEPHONE: 1-800-579-1639 3) 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 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 April 26, 2018 to facilitate timely delivery.

The Board of Directors recommends you vote FOR the following: 1. To elect three Class II Directors, each to serve for a term expiring at the 2021 Annual Meeting of Stockholders: Nominees: 01) John N. Burke 02) Kenneth A. Hoxsie 03) Kathryn P. O'Neil The Board of Directors recommends you vote FOR the following proposals: 2. To ratify the Audit Committee's appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2018. 3. To approve, by non-binding vote, our executive compensation. In their discretion, the named Proxies are authorized to vote upon such other matters as may properly come before the meeting or any adjournment thereof. E38135-P01836 Voting Items

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