SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Columbia Capital IV, LLC (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Millennial Media Inc. [ MM ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 10/29/2012
	4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/29/2012		S		2,202,329(1)	D	$13.4425	11,297,902(2)	I	By Funds(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* Columbia Capital IV, LLC (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (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* Columbia Capital Employee Investors IV, L.P. (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (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* COLUMBIA CAPITAL EQUITY PARTNERS IV QP L P (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (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* COLUMBIA CAPITAL EQUITY PARTNERS IV QPCO L P (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (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* Columbia Capital Equity Partners IV, L.P. (Last) (First) (Middle) C/O COLUMBIA CAPITAL 201 N. UNION STREET, SUITE 300 (Street) ALEXANDRIA VA 22314 (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. The total includes 1,947,092 shares sold by Columbia Capital Equity Partners IV (QP), L.P. ("CCIV (QP)"), 239,565 shares sold by Columbia Capital Equity Partners IV (QPCO), L.P. ("CCIV (QPCO)") and 15,672 shares sold by Columbia Capital Employee Investors IV, L.P. ("CCEI").

2. The total includes 9,988,544 shares held by CCIV (QP), 1,228,961 shares held by CCIV (QPCO) and 80,397 shares held by CCEI.

3. Columbia Capital Equity Partners IV, L.P. ("CCEP") is the general partner of CCIV (QP) and CCIV (QPCO). Columbia Capital IV, LLC ("CC") is the general partner of CCEP and CCEI. Each of CCEP, CC and James B. Fleming, Jr., Harry F. Hopper III and R. Phillip Herget, III, who control CC, may be deemed to beneficially own the reported securities, but each disclaims beneficial ownership of such reported securities except to the extent of its or his pecuniary interest therein. The filing of this statement by any reporting person shall not be deemed an admission that such person is, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the beneficial owner of any equity securities covered by this statement.

Remarks:

	/s/ Donald A. Doering, Executive Vice President of Columbia Capital IV, LLC	10/29/2012
	/s/ Donald A. Doering, Executive Vice President of Columbia Capital IV, LLC, the General Partner of Columbia Capital Employee Investors IV, L.P.	10/29/2012
	/s/ Donald A. Doering, Executive Vice President of Columbia Capital IV, LLC, the General Partner of Columbia Capital Equity Partners IV, L.P., the General Partner of Columbia Capital Equity Partners IV (QP), L.P.	10/29/2012
	/s/ Donald A. Doering, Executive Vice President of Columbia Capital IV, LLC, the General Partner of Columbia Capital Equity Partners IV, L.P., the General Partner of Columbia Capital Equity Partners IV (QPCO), L.P.	10/29/2012
	/s/ Donald A. Doering, Executive Vice President of Columbia Capital IV, LLC, the General Partner of Columbia Capital Equity Partners IV, L.P.	10/29/2012
	** Signature of Reporting Person	Date
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