X0306 4 2021-06-10 0 0001551693 Sientra, Inc. SIEN 0001203567 OBOYLE KEVIN C 420 SOUTH FAIRVIEW AVENUE, SUITE 200 SANTA BARBARA CA 93117 1 0 0 0 Common Stock 2021-06-10 4 A 0 16870 0.00 A 117672 D The Restricted Stock Units shall vest on the earlier to occur of: (i) the day prior to the 2022 Annual Shareholders Meeting or (ii) on the one (1) year anniversary of the Annual Shareholders Meeting on which the Restricted Stock Award was granted, subject to continued service. Each restricted stock unit represents a contingent right to receive one share of Sientra, Inc. Class A Common Stock. /s/ Kevin C. O'Boyle, by Oliver Bennett, as Attorney-in-Fact 2021-06-15