THIS CERTIFIES CUSIP 904311 10 7 THAT IS THE OWNER OF FULLY PAID AND NON-ASSESSABLESHARES OF THE CLASS A COMMON STOCK, PAR VALUE $.00031/3 PER SHARE, OF

Exhibit 4.01

CLASS A

COMMON STOCK

INCORPORATED UNDER THE LAWS OF THE STATE OF MARYLAND

SHARES

See reverse for certain definitions

FULLY PAID AND NON-ASSESSABLE SHARES OF THE CLASS A COMMON STOCK,
PAR VALUE $.0003¹/₃ PER SHARE, OF

Under Armour, Inc. transferable on the books of the Corporation by the holder hereof in person or by duly authorized attorney upon surrender of this certificate properly endorsed. This certificate and the shares represented hereby are issued and shall be held subject to all of the provisions of the Charter of the Corporation, to all of which the holder of this certificate by acceptance hereof expressly assents. This certificate is not valid unless countersigned by the Transfer Agent and registered by the Registrar.

        Witness the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.

                Dated

COUNTERSIGNED AND REGISTERED:

WACHOVIA BANK,N.A.

(Charlotte, NC)

TRANSFER AGENT AND REGISTRAR BY:

AUTHORIZED SIGNATURE

COLORS SELECTED FOR PRINTING: Logo is a vector image, prints in black. Intaglio prints in SC-7 Dark Blue.

COLOR: This proof was printed from a digital file or artwork on a graphics quality, color laser printer. It is a good representation of the color as it will appear on the final product. However, it is not an exact color rendition, and the final printed product may appear slightly different from the proof due to the difference between the dyes and printing ink.

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The Corporation currently has authorized for issuance Class A Common Stock and Class B Common Stock and is also authorized to issue additional classes or series of Common Stock or Preferred Stock on such terms as shall be determined by the Board of Directors. The Corporation will furnish to any stockholder on request and without charge a full statement of the designations and any preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends, qualifications, and terms and conditions of redemption of the stock of each class or series that the corporation is authorized to issue and the differences in the relative rights and preferences between the shares of each series of stock to the extent that they have been set.

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:

Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED,                          hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER

IDENTIFYING NUMBER OF ASSIGNEE

Please print or typewrite name and address including postal zip code of assignee

of the Capital Stock represented by the within Certificate and do hereby irrevocably constitute and appoint

___________________________________________________________________________________ Attorney to transfer the said stock on the books of the within named Corporation with full power of substitution in the premises.

Dated ____________________

KEEP THIS CERTIFICATE IN A SAFE PLACE. IF IT IS LOST, STOLEN, MUTILATED OR DESTROYED, THE CORPORATION MAY REQUIRE A BOND OF INDEMNITY AS A CONDITION TO THE ISSUANCE OF A REPLACEMENT CERTIFICATE.

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NOTE:TEXT RECEIVED BY MODEM OR E-MAIL IS NOT PROOFREAD WORD FOR WORD.

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