X0206 3 2018-01-17 0 0001453593 Xtant Medical Holdings, Inc. XTNT 0001055951 ORBIMED ADVISORS LLC 601 LEXINGTON AVENUE, 54TH FLOOR NEW YORK NY 10022 0 0 1 0 0001055949 ISALY SAMUEL D 601 LEXINGTON AVENUE, 54TH FLOOR NEW YORK NY 10022 0 0 1 0 Common Stock 1927977 I See Footnotes Common Stock 823207 I See Footnotes Warrant to Purchase Common Stock 6.40 2013-12-05 2020-12-05 Common Stock 87719 I See Footnotes Convertible Note 3.88 2021-07-15 Common Stock 33190000 I See Footnotes Convertible Note 3.88 2021-07-15 Common Stock 18810000 I See Footnotes Convertible Note 2.90 2021-07-15 Common Stock 1428553 I See Footnotes Convertible Note 2.90 2021-07-15 Common Stock 809614 I See Footnotes These securities are held of record by ROS Acquisition Offshore LP ("ROS Acquisition"). OrbiMed Advisors LLC ("Advisors"), a registered adviser under the Investment Advisors Act of 1940, as amended, is the investment manager of ROS Acquisition. Samuel D. Isaly ("Isaly"), a natural person, is the managing member of, and holder of a controlling interest in, Advisors. Advisors is also the investment manager of Royalty Opportunities S.a r.l., of which ROS Acquisition is a wholly-owned subsidiary. By virtue of such relationships, Advisors and Isaly may be deemed to have voting and investment power with respect to the securities held by ROS Acquisition noted above and as a result may be deemed to have beneficial ownership over such securities. These securities are held of record by OrbiMed Royalty Opportunities II, LP ("ORO II"). OrbiMed ROF II LLC ("ROF II") is the sole general partner of ORO II, and Advisors is the sole managing member of ROF II. Isaly, a natural person, is the managing member of, and holder of a controlling interest in, Advisors. By virtue of such relationships, Advisors and Isaly may be deemed to have voting and investment power with respect to the securities held by ORO II noted above and as a result may be deemed to have beneficial ownership over such securities. This report on Form 3 is jointly filed by Advisors and Isaly. Each of the reporting persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its or his pecuniary interest therein, if any. This report shall not be deemed an admission that any of the reporting persons is a beneficial owner of such securities for the purposes of Section 16 of the Exchange Act, or for any other purposes. These convertible notes (collectively, the "Notes") may be converted into shares of common stock ("Shares") of the Issuer at any time prior to the close of business on the second business day immediately preceding July 15, 2021. However, the Notes will not be convertible to the extent that such conversion would result in the holder of each Note or any of its affiliates being deemed to beneficially own in excess of 9.99% of the then-outstanding Shares. Pursuant to the Restructuring and Exchange Agreement entered into on January 11, 2018 among the Issuer, ORO II, ROS Acquisition and certain other parties, which agreement is filed as an exhibit to the Issuer's Form 8-K filed with the Securities and Exchange Commission on January 12, 2018 (the "Form 8-K"), the Issuer, ORO II and ROS Acquisition have agreed to amend the Notes to clarify that the restriction that prevents any holder or any of its affiliates from effecting a conversion thereof if such conversion would result in the holder or any of its affiliates beneficially owning in excess of 9.99% of the then-outstanding Shares shall not be applicable to the Tier 2 Transaction (as described in the Form 8-K). /s/ Samuel D. Isaly 2018-01-19