13G Filing: Boxer Capital, LLC and Macrogenics Inc (MGNX)

---

(ii)

Shared power to vote or to direct the vote:

The Reporting Persons have shared power to vote
or to direct the vote of the 1,987,000 shares of Common Stock they beneficially own.

(iii)

Sole power to dispose or to direct the disposition of:

None of the Reporting Persons has the
sole power to dispose or to direct the disposition of any of the shares of Common Stock the Reporting Persons beneficially own.

(iv)

Shared power to dispose or to direct the disposition of:

The Reporting Persons have shared
power to dispose or to direct the disposition of the 1,987,000 shares of Common Stock they beneficially own.

*	Based on 36,112,593 shares of common stock reported to be outstanding on the Issuers Prospectus Supplement filed with the Securities and Exchange Commission on April 27, 2017.

Item 5. Ownership of Five Percent or Less of a Class.

Not applicable.

Item 6. Ownership of
More than Five Percent on Behalf of Another Person.

Only Boxer Capital has the right to receive dividends and the proceeds from the
sale of the shares of Common Stock held by Boxer Capital. See Item 4 above.

Item 7. Identification and Classification of the Subsidiary
Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not applicable.

Item 8. Identification and Classification of Members of the Group.

Not applicable.

Item 9. Notice of
Dissolution of Group.

Not applicable.

Item 10. Certification.

(c) By
signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities
and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

Exhibits

1

Joint Filing Agreement, dated June 12, 2017, among the Reporting Persons.