SEC Form 3
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
or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person*
MPM BioVentures IV QP LP

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLAREDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
05/30/2013
3. Issuer Name and Ticker or Trading Symbol
Epizyme, Inc. [ EPZM ]
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 of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
Form filed by One Reporting Person
X Form filed by More than One Reporting Person
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)
Common Stock 178,331(1) I See Footnote(2)
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: 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 A Preferred Stock (3) (3) Common Stock 2,309,998 (3) I See Footnote(4)
Series B Preferred Stock (5) (5) Common Stock 392,156 (5) I See Footnote(6)
1. Name and Address of Reporting Person*
MPM BioVentures IV QP LP

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLAREDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
Scopa James Paul

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
601 GATEWAY BLVD., SUITE 350

(Street)
SOUTH SAN FRANCISCO CA 94080

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
Vander Vort John

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
MPM Asset Management Investors BV4 LLC

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
MPM BioVentures IV GmbH & Co. Beteiligungs KG

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
MPM BioVentures IV GP LLC

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
MPM BioVentures IV Strategic Fund, L.P.

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
MPM BioVentures IV LLC

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
Foley Todd

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
KAILIAN VAUGHN M

(Last) (First) (Middle)
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR

(Street)
BOSTON MA 02116

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
Explanation of Responses:
1. Reflects a one-for-three reverse stock split effected May 13, 2013.
2. The shares are held as follows: 166,007 by MPM BioVentures IV-QP, L.P. ("BV IV QP"), 6,395 by MPM BioVentures IV GmbH & Co. Beteiligungs KG ("BV IV KG"), 4,720 by MPM Asset Management Investors BV4 LLC ("AM BV4") and 1,209 shares held by MPM BioVentures IV Strategic Fund, L.P. ("BV IV SF"). MPM BioVentures IV GP LLC and MPM BioVentures IV LLC ("BV LLC") are the direct and indirect general partners of BV IV QP, BV IV KG and BV IV SF and BV LLC is the manager of AM BV4. Ansbert Gadicke, Luke Evnin, Vaughn M. Kailian,James Paul Scopa, Todd Foley and John Vander Vort are the members of BV LLC. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.
3. Each share of Series A Preferred Stock is convertible into 1/3rd of a share of Common Stock without payment of further consideration and will automatically convert into 1/3rd 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. The shares are held as follows: 1,850,799 by BV IV QP, 71,303 by BV IV KG, 52,628 by AM BV4 and 335,268 shares held by BV IV SF. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.
5. Each share of Series B Preferred Stock is convertible into 1/3rd of a share of Common Stock without payment of further consideration and will automatically convert into 1/3rd 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.
6. The shares are held as follows: 312,152 by BV IV QP, 12,026 by BV IV KG, 8,876 by AM BV4 and 59,102 shares held by BV IV SF. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.
Remarks:
See Form 3 for Luke Evnin for additional members of this joint filing.
By Luke Evnin, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC, the general partner of MPM BioVentures IV-QP, L.P. /s/ Luke Evnin 05/30/2013
/s/ James P. Scopa 05/30/2013
/s/ John Vander Vort 05/30/2013
By Luke Evnin, member of MPM BioVentures IV LLC, the manager of MPM Asset Management Investors BV4 LLC /s/ Luke Evnin 05/30/2013
By Luke Evnin, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC, the managing limited partner of MPM BioVentures IV GmbH & Co. Beteiligungs KG /s/ Luke Evnin 05/30/2013
By Luke Evnin, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC /s/ Luke Evnin 05/30/2013
By Luke Evnin, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC, the general partner of MPM BioVentures IV Strategic Fund, L.P. /s/ Luke Evnin 05/30/2013
By Luke Evnin, member of MPM BioVentures IV LLC /s/ Luke Evnin 05/30/2013
/s/ Todd Foley 05/30/2013
/s/ Vaughn Kailian 05/30/2013
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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