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 *
  ADVENT PRIVATE EQUITY FUND III A LTD PARTNERSHIP
 2. Date of Event Requiring Statement (Month/Day/Year)
05/05/2006		 3. Issuer Name and Ticker or Trading Symbol
MICROMET, INC. [MITI]
(Last)
(First)
(Middle)
25 BUCKINGHAM GATE		 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)

LONDON, X0 SW1E 6LD		 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)
common stock (1) 3,528,875 (2) (3)
D (2) (3)
 

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

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
ADVENT PRIVATE EQUITY FUND III A LTD PARTNERSHIP
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT PRIVATE EQUITY FUND III B LTD PARTNERSHIP
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT PRIVATE EQUITY FUND III C LTD PARTNERSHIP
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT PRIVATE EQUITY FUND III D LTD PARTNERSHIP
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT PRIVATE EQUITY FUND III GMBH & CO KG
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT PRIVATE EQUITY FUND III AFFILIATES
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    
ADVENT MANAGEMENT III L P
25 BUCKINGHAM GATE
LONDON, X0 SW1E 6LD		     X    

Signatures

/s/ Cara L. Hupprich, Attorney-in-fact 05/15/2006
**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) All shares reported herein are shown after the effects of a 1-for-3 reverse stock split effected by the Issuer on May 5, 2006.
(2) Consists of: (i) 1,785,787 shares held of record by Advent Private Equity Fund III ?A? Limited Partnership; (ii) 874,759 shares held of record by Advent Private Equity Fund III ?B? Limited Partnership; (iii) 244,118 shares held of record by Advent Private Equity Fund III ?C? Limited Partnership; (iv) 480,071 shares held of record by Advent Private Equity Fund III ?D? Limited Partnership; (v) 69,111 shares held of record by Advent Private Equity Fund III GmbH & Co. KG; (vi) 57,189 shares held of record by Advent Private Equity Fund III Affiliates Limited Partnership; and (vii) 17,840 shares held of record by Advent Management III Limited Partnership. This report is filed jointly by each of the foregoing entities, all of which are ten percent owners.
(3) In addition, Jerry Benjamin, a general partner of each of the foregoing entities, may be deemed to beneficially own the shares held by the foregoing entitiies. Mr. Benjamin is also a director of the Issuer and has reported his beneficial ownership separately on a Form 3 and Form 4, both of which were filed on May 9, 2006. Each of the filing persons disclaims beneficial ownership of the shares reported herein except to the extent of its pecuniary interest therein.

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