SIEN Sientra Inc

*As of June 14, 2019 (the “ Filing Date ”), Abingworth LLP (“ Abingworth ”) may be deemed to beneficially own an aggregate of 2,435,542 shares of common stock, $0.01 par value per share (“ Common Stock ”), of Sientra, Inc. (the “ Issuer ”). The number of shares of Common Stock reported above consists of (i)  1,195,421 shares of Common Stock held by Abingworth Bioventures V, LP (“ ABV V ”), (ii)  1,195,422 shares of Common Stock held by Abingworth Bioventures V Co-Invest Growth Equity Fund, LP (“ AGE ” and together with ABV V, the “ Abingworth Funds ”), (iii) 37,662 shares of Common Stock held by Timothy Haines, a director of the Issuer and (iv) 7,037 shares of Common Stock issuable within 60 days of the Filing Date upon exercise of Options (the “Options”) held by Timothy Haines. Abingworth, as the investment manager of the Abingworth Funds, may be deemed to beneficially own the 2,390,843 shares of Common Stock held by the Abingworth Funds. Under an agreement between Mr. Haines and Abingworth, Mr. Haines is deemed to hold the Common Stock, Options and any Common Stock issuable upon exercise of the Options for the benefit of the Abingworth Funds, and must exercise the Options solely upon the direction of Abingworth, as a result of which each of ABV V, AGE and Abingworth may be deemed to beneficially own any Common Stock and Common Stock issuable upon exercise of the Options owned by Mr. Haines. Thus, as of the Filing Date, for purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), Abingworth may be deemed to beneficially own 2,435,542 shares of Common Stock of the Issuer or approximately 4.9% of the shares of Common Stock deemed issued and outstanding. This Amendment constitutes an exit filing.

The foregoing beneficial ownership percentage is based upon 49,201,650 shares of Common Stock issued and outstanding as of June 7, 2019, based on information from the Issuer and other public information.

Explanatory Note

This Amendment No. 2 (the “ Amendment ”) amends and supplements the Schedule 13D filed by the Reporting Person (as defined in the Schedule 13D) with the Securities and Exchange Commission (the “ SEC ”) on November 7, 2014, as amended on May 9, 2018 (the “ Schedule 13D ”). This Schedule 13D, as amended by this Amendment relates to the shares of common stock, $0.01 par value per share (“ Common Stock ”), of Sientra, Inc., a Delaware corporation (the “ Issuer ”). Except as specifically provided herein, this Amendment does not modify or amend any of the information previously reported in the Schedule 13D. Capitalized terms used and not otherwise defined herein shall have the meanings ascribed to such terms in the Schedule 13D.

This Amendment constitutes an exit filing for Reporting Person as Abingworth owns less than five percent (5%) of the shares of Common Stock of Issuer.

Item 5.     Interest in Securities of the Issuer

Item 5 of the Schedule 13D is hereby amended by deleting it in its entirety and substituting the following in lieu thereof:

As of the Filing Date, Abingworth may be deemed to beneficially own an aggregate of 2,435,542 shares of Common Stock. 1,195,421 shares of Common Stock are held directly by ABV V, 1,195,422 shares of Common Stock are held directly by AGE, 37,662 shares of Common Stock issued to Timothy Haines and 7,037 shares of Common Stock issuable upon exercise of Options (the “ Options ”) held by Mr. Haines.

Abingworth is not the owner of record of any shares of Common Stock. Abingworth, as the investment manager to the Abingworth Funds, may be deemed to beneficially own, in the aggregate, 2,435,542 shares of Common Stock, representing approximately 4.9% of the shares of Common Stock of the Issuer deemed issued and outstanding as of the Filing Date. The foregoing beneficial ownership percentage is based upon 49,201,650 shares of Common Stock issued and outstanding as of June 7, 2019, based on information from the Issuer and other public information.

As set forth in the cover sheet to this Schedule 13D, (i) ABV V has shared voting and dispositive power with respect to the 1,195,421 shares of Common Stock held by ABV V, and does not have sole voting and dispositive power over any of the securities reported herein; (ii) AGE has shared voting and dispositive power with respect to the 1,195,422 shares of Common Stock held by AGE, and does not have sole voting and dispositive power over any of the securities reported herein; and (iii) Abingworth has shared voting and dispositive power with respect to the 2,390,843 shares of Common Stock held by the Abingworth Funds, and does not have sole voting and dispositive power over any of the securities reported herein.

Mr. Haines owns 37,662 shares of Common Stock and has been issued to date, 7,037 shares of Common Stock issuable upon exercise of Options (the “Options”) in connection with his service as a member of the Board. Abingworth provides advisory services to ABV V. Under an agreement between Mr. Haines and Abingworth, Mr. Haines is deemed to hold the shares of Common Stock, Options and any shares of Common Stock issuable upon exercise of the Options for the benefit of the Abingworth Funds, and must exercise the Options solely upon the direction of Abingworth. 7,037 Options were exercisable as of the Event Date (as defined below) and as of Filing Date.

Except as described herein, during the past sixty (60) days on or prior to June 7, 2019 (the “ Event Date ”), and from the Event Date to the Filing Date, there were no purchases or sales of shares of Common Stock, or securities convertible into or exchangeable for shares of Common Stock, by the Reporting Person or any person or entity for which the Reporting Person possess voting or dispositive control over the securities thereof.

Each Abingworth Fund has the right to receive dividends from, or proceeds from the sale of, the shares of Common Stock owned by it. The partners of each Abingworth Fund have the right to participate indirectly in the receipt of dividends from, or proceeds from the sale of, the shares of Common Stock held by the Abingworth Funds, in accordance with their respective ownership interests in such Abingworth Fund. 

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated:  June 17, 2019

Attention: Intentional misstatements or omissions of fact constitute
Federal criminal violations (See 18 U.S.C. 1001).