Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  ALTA BIOPHARMA PARTNERS III LP
2. Date of Event Requiring Statement (Month/Day/Year)
10/09/2013
3. Issuer Name and Ticker or Trading Symbol
MACROGENICS INC [MGNX]
(Last)
(First)
(Middle)
ONE EMBARCADERO CENTER, 37TH FLOOR
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SAN FRANCISCO, CA 94111
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Series B Convertible Preferred Stock   (1)   (1) Common Stock 18,728,346 $ (1) I ABP III, ABP III KG, AEBP III (2)
Series C Convertible Preferred Stock   (3)   (3) Common Stock 12,328,024 $ (3) I ABP III, ABP III KG, AEBP III (4)
Series D-2 Convertible Preferred Stock   (3)   (3) Common Stock 3,833,767 $ (3) I ABP III, ABP III KG, AEBP III (5)
Series D-2 Convertible Preferred Warrants   (6)   (7) Common Stock 287,533 (3) $ (3) I ABP III, ABP III KG, AEBP III (8)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
ALTA BIOPHARMA PARTNERS III LP
ONE EMBARCADERO CENTER
37TH FLOOR
SAN FRANCISCO, CA 94111
    X    
ALTA BIOPHARMA PARTNERS III GMBH & CO BETEILIGUNGS KG
ONE EMBARCADERO CENTER
37TH FLOOR
SAN FRANCISCO, CA 94111
    X    
ALTA EMBARCADERO BIOPHARMA PARTNERS III LLC
ONE EMBARCADERO CENTER
37TH FLOOR
SAN FRANCISCO, CA 94111
    X    

Signatures

/s/ Edward Hurwitz 10/09/2013
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each share of Series B Convertible Preferred Stock is convertible into 0.0607 of a share of Common Stock without payment of further consideration and will automatically convert into 0.0607 of a share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. The shares have no expiration date.
(2) These securities are held as follows: 17,153,592 by Alta BioPharma Partners III, L.P. ("ABP III") , 1,152,018 by Alta BioPharma Partners III LP GmbH ("ABP III KG") and 422,736 by Alta Embarcadero BioPharma Partners III, LLC ("AEBP III"). Alta BioPharma Management Partners III, LLC ("ABMP") is the general partner of ABP III, the managing limited partner of ABP III KG and the manager of AEBP III. ABMP disclaims beneficial ownership of these securities except to the extent of any pecuniary interest therein.
(3) Each share of Series C Convertible Preferred Stock and each share of Series D-2 Convertible Preferred Stock is convertible into 0.0533 of a share of Common Stock without payment of further consideration and will automatically convert into 0.0533 of a share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. The shares have no expiration date.
(4) These securities are held as follows: 11,291,435 by ABP III , 758,321 by ABP III KG and 278,268 by AEBP III. ABMP is the general partner of ABP III, the managing limited partner of ABP III KG and the manager of AEBP III. ABMP disclaims beneficial ownership of these securities except to the extent of any pecuniary interest therein.
(5) These securities are held as follows: 3,511,408 by ABP III , 235,823 by ABP III KG and 86,536 by AEBP III. ABMP is the general partner of ABP III, the managing limited partner of ABP III KG and the manager of AEBP III. ABMP disclaims beneficial ownership of these securities except to the extent of any pecuniary interest therein.
(6) Immediately.
(7) The warrants will expire upon the closing of the initial public offering.
(8) These securities are held as follows: 263,356 by ABP III , 17,687 by ABP III KG and 6,490 by AEBP III. ABMP is the general partner of ABP III, the managing limited partner of ABP III KG and the manager of AEBP III. ABMP disclaims beneficial ownership of these securities except to the extent of any pecuniary interest therein.

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