SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Schedule 13G

(Rule 13d-102)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1 (b), (c) AND (d)

AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2 (b)

(Amendment No. 1)*

comScore, Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

20564W105

(CUSIP Number)

December 31, 2010

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)

¨ Rule 13d-1(c)

x Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(Continued on following pages)

Page 1 of 16

Exhibit Index Contained on Page 14

CUSIP NO. 20564W105

13 G

Page 2 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Accel VII L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 0 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0%
12	TYPE OF REPORTING PERSON PN

CUSIP NO. 20564W105

13 G

Page 3 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Accel VII Associates L.L.C.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 0 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0%
12	TYPE OF REPORTING PERSON OO

CUSIP NO. 20564W105

13 G

Page 4 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Accel Internet Fund III L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 0 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0%
12	TYPE OF REPORTING PERSON PN

CUSIP NO. 20564W105

13 G

Page 5 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Accel Internet Fund III Associates L.L.C.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 0 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0%
12	TYPE OF REPORTING PERSON OO

CUSIP NO. 20564W105

13 G

Page 6 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Accel Investors ’99 L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 0 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 0 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0%
12	TYPE OF REPORTING PERSON PN

CUSIP NO. 20564W105

13 G

Page 7 of 16 Pages

1	NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON James W. Breyer
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 2,702 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 2,702 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,702
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0%
12	TYPE OF REPORTING PERSON IN

CUSIP NO. 20564W105

13 G

Page 8 of 16 Pages

1	NAME OF REPORTING PERSONS SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS Arthur C. Patterson
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 255,444 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 255,444 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 255,444
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.8%
12	TYPE OF REPORTING PERSON IN

CUSIP NO. 20564W105

13 G

Page 9 of 16 Pages

1	NAME OF REPORTING PERSONS SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS Theresia Gouw Ranzetta
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 2,489 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 2,489 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,489
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0%
12	TYPE OF REPORTING PERSON IN

CUSIP NO. 20564W105

13 G

Page 10 of 16 Pages

1	NAME OF REPORTING PERSONS SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS James R. Swartz
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 119,597 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 119,597 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 119,597
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.4%
12	TYPE OF REPORTING PERSON IN

CUSIP NO. 20564W105

13 G

Page 11 of 16 Pages

1	NAME OF REPORTING PERSONS SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS J. Peter Wagner
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3	SEC USE ONLY
4	CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		5	SOLE VOTING POWER 2,467 shares.
		6	SHARED VOTING POWER 0 shares.
		7	SOLE DISPOSITIVE POWER 2,467 shares.
		8	SHARED DISPOSITIVE POWER 0 shares.
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,467
10	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0%
12	TYPE OF REPORTING PERSON IN

Page 12 of 16

This Amendment No. 1 amends the statement on Schedule 13G filed by Accel VII L.P., a Delaware limited partnership (“A7”), Accel VII Associates L.L.C., a Delaware limited liability company and the general partner of A7 (“A7A”), Accel Internet Fund III L.P., a Delaware limited partnership (“AIF3”), Accel Internet Fund III Associates, L.L.C., a Delaware limited liability company and the general partner of AIF3 (“AIF3A”), and Accel Investors ’99 L.P., a Delaware limited partnership (“AI99”), James W. Breyer (“Breyer”), a general partner of AI99 and a managing member of A7A and AIF3A, Arthur C. Patterson (“Patterson”), a general partner of AI99 and a managing member of A7A and AIF3A, Theresia Gouw Ranzetta (“Ranzetta”), a general partner of AI99 and a managing member of A7A and AIF3A, James R. Swartz (“Swartz”), a general partner of AI99 and a managing member of A7A and AIF3A, and J. Peter Wagner (“Wagner”), a general partner of AI99 and a managing member of A7A and AIF3A. The foregoing entities and individuals are collectively referred to as the “Reporting Persons.” Only those items to which there has been a change are included in this Amendment No. 1.

ITEM 4.

OWNERSHIP:

The following information with respect to the ownership of the Common Stock of the issuer by the persons filing this Statement is provided as of December 31, 2010:

(a)

Amount beneficially owned:

See Row 9 of cover page for each Reporting Person.

(b)

Percent of Class:

See Row 11 of cover page for each Reporting Person.

(c)

Number of shares as to which such person has:

(i)

Sole power to vote or to direct the vote:

See Row 5 of cover page for each Reporting Person.

(ii)

Shared power to vote or to direct the vote:

See Row 6 of cover page for each Reporting Person.

(iii)

Sole power to dispose or to direct the disposition of:

See Row 7 of cover page for each Reporting Person.

(iv)

Shared power to dispose or to direct the disposition of:

See Row 8 of cover page for each Reporting Person.

ITEM 5.

OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: x Yes

Page 13 of 16

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: February 10, 2011

Entities:

Accel VII L.P.
Accel Internet Fund III L.P.
Accel Investors ‘99 L.P.
Accel VII Associates L.L.C.	By:	/s/ Tracy L. Sedlock
Accel Internet Fund III Associates L.L.C.		Tracy L. Sedlock, Attorney-in-fact
		for above-listed entities
Individuals:

James W. Breyer
Arthur C. Patterson
Theresia Gouw Ranzetta	By:	/s/ Tracy L. Sedlock
James R. Swartz		Tracy L. Sedlock, Attorney-in-fact
J. Peter Wagner		for above-listed individuals

Page 14 of 16

EXHIBIT INDEX

		Found on
		Sequentially
Exhibit		Numbered Page

Exhibit A: Agreement of Joint Filing		15

Exhibit B: Reference to Tracy L. Sedlock as Attorney-in-Fact		16

Page 15 of 16

EXHIBIT A

Agreement of Joint Filing

The Reporting Persons hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Common Stock of comScore, Inc. shall be filed on behalf of each of the Reporting Persons. Note that copies of the applicable Agreement of Joint Filing are already on file with the appropriate agencies.

Page 16 of 16

EXHIBIT B

REFERENCE TO TRACY L. SEDLOCK AS ATTORNEY-IN-FACT

Tracy L. Sedlock has signed the enclosed documents as Attorney-In-Fact. Note that a copy of the applicable Power of Attorney is already on file with the appropriate agencies.

ACCEL VII LP SC 13G/A