X0306 4 2017-02-22 0 0001114995 IMPINJ INC PI 0001184752 ALBERG TOM A 999 THIRD AVENUE 34TH FLOOR SEATTLE WA 98104 1 0 0 0 Common Stock 2017-02-22 4 J 0 969886 0.00 D 235551 I See footnote Common Stock 2017-02-22 4 J 0 105649 0.00 D 129902 I See footnote Common Stock 2017-02-22 4 J 0 129902 0.00 D 0 I See footnote Common Stock 2017-02-22 4 J 0 42151 0.00 A 77865 D Common Stock 2017-02-22 4 J 0 31489 0.00 A 109354 D Common Stock 2017-02-22 4 J 0 1415 0.00 A 110769 D Common Stock 2017-02-22 4 J 0 4817 0.00 A 4817 I By Alberg Family Investments LLC Common Stock 2017-02-22 4 J 0 31219 0.00 A 31219 I By Raven Trust Fund Pro rata distribution from Madrona Venture Fund I-A, LP, of which the reporting person is a managing member. 129,902 of these shares are held by Madrona Managing Director Fund, LLC and 105,649 of these shares are held of record by Madrona Venture Fund I-B, L.P. Madrona Investment Partners, LLC, as the sole general partner of Madrona Venture Fund I-A, L.P. and Madrona Venture Fund I-B, L.P., may be deemed to beneficially own certain of the shares held of record by Madrona Venture Fund I-A, L.P. and Madrona Venture Fund I-B, L.P. but disclaims beneficial ownership of such shares in which it does not have an actual pecuniary interest. Tom A. Alberg, a member of the board of directors, disclaims beneficial ownership of all shares held of record by Madrona Managing Director Fund, LLC, Madrona Venture Fund I-A, L.P. and Madrona Venture Fund I-B, L.P., in which he does not have an actual pecuniary interest. By virtue of their relationship as affiliated entities who have overlapping general partners and managing directors, Madrona Managing Director Fund, LLC, Madrona Venture Fund I-A, L.P., Madrona Venture Fund I-B, L.P., Madrona Investment Partners, LLC and Mr. Alberg may be deemed to share voting and investment control of the record shares. Pro rata distribution from Madrona Venture Fund I-B, L.P., of which the reporting person is a managing member. Represents 129,902 shares held by Madrona Managing Director Fund, LLC. Pro rata distribution from Madrona Managing Director Fund, LLC, of which the reporting person is a managing member. Pro rata distribution from Madrona Investment Partners, LLC, of which the reporting person is a managing member. Shares held of record by the Alberg Family Investments LLC. Mr. Alberg shares voting and dispositive control over such shares but disclaims beneficial ownership over such shares. Shares held of record by Raven Trust Fund. Mr. Alberg shares voting and dispositive control over such shares but disclaims beneficial ownership over such shares. Yukio Morikubo, as Attorney in fact for Tom Alberg 2017-02-23