X0306 4 2018-11-05 0 0001438133 TANDEM DIABETES CARE INC TNDM 0001582779 Allen Dick C/O TANDEM DIABETES CARE, INC., 11075 ROSELLE STREET SAN DIEGO CA 92121 1 0 0 0 Common Stock 2018-11-05 4 S 0 82 37.96 D 2418 I See Footnote Common Stock 2018-11-05 4 S 0 82 37.88 D 2418 I See Footnote Common Stock 2018-11-05 4 S 0 3898 37.75 D 18103 I See Footnote Common Stock 2018-11-05 4 S 0 11160 38.11 D 52000 I See Footnote The securities are held by the Gammon Children's 2000 Trust FBP Jake Allen Gammon. The Reporting Person is co-trustee of the Gammon Children's 2000 Trust FBO Jake Allen Gammon and has shared voting and investment power over the securities held by the Gammon Children's 2000 Trust FBO Jake Allen Gammon and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by the Gammon Children's 2000 Trust FBO Jake Allen Gammon. The securities are held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon. The Reporting Person is co-trustee of the Gammon Children's 2000 Trust FBO Hannah Lee Gammon and has shared voting and investment power over the securities held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon. The price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $37.72 and $37.79. The securities are held by Allen Cornerstone Ventures L.P. The Reporting Person is the managing partner of Allen Cornerstone Ventures L.P. and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by Allen Cornerstone Ventures L.P., except to the extent of his proportionate pecuniary interest therein. The price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $37.66 and $38.68. The securities are held by the Allen Family Trust dated October 12, 1981. s/ David B. Berger, Attorney-in-Fact for Dick P. Allen 2018-11-06