COMMON STOCK COMMON STOCK FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK, $0.001 PAR VALUE PER SHARE, OF MILLENNIAL MEDIA, INC. transferable on the books of the Corporation in person or by duly authorized attorney upon surrender of the Certificate properly endorsed. This Certificate shall not be valid until countersigned by the Transfer Agent and registered by the Registrar. WITNESS the facsimile signatures of the Corporation’s duly authorized officers. Dated: TREASURER PRESIDENT AND CHIEF EXECUTIVE OFFICER COUNTERSIGNED AND REGISTERED: AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC (Brooklyn, N.Y.) TRANSFER AGENT AND REGISTRAR BY AUTHORIZED SIGNATURE INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE SEE REVERSE FOR CERTAIN DEFINITIONS CUSIP 60040N 10 5 This Certifies that is the record holder of MM

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: TEN COM TEN ENT JT TEN as tenants in common as tenants by the entireties as joint tenants with right of survivorship and not as tenants in common UNIF GIFT MIN ACT– Custodian (Cust) (Minor) under Uniform Gifts to Minors Act (State) Additional abbreviations may also be used though not in the above list. – of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint to transfer the said stock on the books of the within named Corporation with full power of substitution in the premises. Dated FOR VALUE RECEIVED, hereby sell, assign and transfer unto PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE Shares Attorney THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME(S) AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER. NOTICE: (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) By THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15. Signature(s) Guaranteed