Exhibit 10.01

Certain portions hereof denoted with “[***]” have been omitted pursuant to a
Request for Confidential Treatment and have

been filed separately with the Commission

SECOND AMENDMENT TO OFFICE LEASE

THIS SECOND AMENDMENT TO OFFICE LEASE (“Second Amendment”) dated as of the 1st
day of October, 2009, by and between BEASON PROPERTIES LLLP, a Maryland limited
liability limited partnership and successor to 1450 BEASON STREET LLC, a
Maryland limited liability company (the “Landlord”) and UNDER ARMOUR, INC., a
Maryland corporation (the “Tenant”).

RECITALS:

WHEREAS, Landlord and Tenant entered into an Office Lease dated December 14,
2007 (the “Original Lease”) for the lease of space in the “Building” (as defined
in the Original Lease, The Overflo Building located at 1450 Beason Street,
Baltimore, Maryland); and

WHEREAS, the Original Lease was modified by that certain First Amendment to
Office Lease dated June 4, 2008 (the “First Amendment” which together with the
Original Lease constitutes the “Current Lease”); and

WHEREAS, Landlord and Tenant now desire to modify certain terms and conditions
set forth in the Current Lease as provided hereinafter (and the Current Lease,
as amended by this Second Amendment, will constitute the “Lease” for all
purposes); and

WHEREAS, in the event of any conflict between the terms of the Current Lease and
this Second Amendment, the Second Amendment provisions will govern.

NOW, THEREFORE, in consideration of the foregoing and of other consideration,
the receipt and adequacy of which is acknowledged, Landlord and Tenant mutually
agree as follows:

1. Definitions. Terms defined in the Original Lease will have the same meaning
for purposes of this Second Amendment, unless modified below:

1.1. “Base Operating Costs” will be based on Operating Costs incurred for the
2010 calendar year.

1.2. “Base Taxes” will be based, initially, on the 2010 state fiscal tax year,
and then reset in accordance with Section 1.1 of the Original Lease.

1.3. “Lease Year” means (a) as to Lease Year 1, the period commencing on
November 1, 2009 and terminating on December 31, 2010, and (b) each successive
period of twelve (12) calendar months thereafter during the Term.

1.4. “Operating Costs” shall not include (in addition to all other exclusions
set forth in the Original Lease) any amounts payable to any Mortgagee in
connection with any work performed on the Building, whether treated as debt
service, reimbursements or otherwise.

1.5. “Premises” shall include the rights of Tenant under a certain Declaration
of Easement executed simultaneously with this Second Amendment and to be
recorded in the land records of Baltimore City. No Rent will attributable to
such rights, except to

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the extent properly included as an Increased Operating Expense as to which
Tenant is obligated to pay Tenant’s Proportionate Share.

1.6. “Rent Commencement Date” means November 1, 2009.

1.7. “Rent Increase Date” means January 1, 2010.

2. The Premises. The Premises is no longer separated into a Phase I Premises, a
Phase II Premises and a Phase III Premises (the “Obsolete Distinctions”). All
such Obsolete Distinctions will either be treated as referring to the Premises
in their entirety or deemed deleted, as the circumstances require.

3. Term. The Original Term shall (a) begin on (i) November 1, 2009, as to the
portion of the Premises made available to Tenant on October 1, 2009, and
(ii) January 1, 2010 as to the entire Premises, and (b) end on December 31,
2015. The three paragraphs in Section 3.1 of the Original Lease that refer to
the Obsolete Distinctions are hereby deleted. This provision will also replace
Section 3.2 of the Original Lease.

4. Rent.

4.1. The last paragraph of Section 4.1(a) of the Original Lease is hereby
deleted.

4.2. Landlord will provide all services required by the Original Lease during
the period October 1, 2009 through October 31, 2009 so as to permit Tenant to
move into the Premises then made available to Tenant.

4.3. For the period between the Rent Commencement Date and the Rent Increase
Date, Base Rent shall be $*** Per Square Foot multiplied by the actual rentable
square footage of the portion of the Premises delivered to Tenant on October 1,
2009 and divided by twelve (12) to establish the amount of Base Rent to be paid
on a monthly basis (and pro-rated as necessary for any period of less than a
calendar month). No Additional Rent will be payable during such period, except
as noted in Sections 4.8 and 7 below.

4.4. At the Rent Increase Date, the Base Rent of $*** Per Square Foot shall
apply to all of the Premises.

4.5. The calculation of Tenant’s Share of Increased Operating Costs will begin
with the comparison of Operating Costs for 2010 with Landlord’s estimate of
Operating Costs for 2011, for the purpose of initiating such payments of
Additional Rent during calendar year 2011.

4.6. With the exception of the first sentence thereof, Section 4.4.1. of the
Original Lease is hereby deleted.

4.7. All payments of Rent are to be made directly to M&T Bank, to such accounts
as are designated by Landlord and M&T Bank.

4.8. Beginning on the Rent Commencement Date, Tenant shall pay the Tenant
Electric as to such portion of the Premises as has been made available to Tenant
on October 1, 2009. Tenant shall pay the Tenant Electric for the balance of the
Premises from the Rent Increase Date.

 

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5. Taxes. Unless the Building is assessed as fully renovated and tenanted for
the fiscal year ending June 30, 2010, Base Taxes will be reset based on such
fully renovated and tenanted reassessment only when it does occur. As an
example, if a reassessment based on a fully renovated and tenanted building does
occur during calendar year 2010, no payment by Tenant for Increased Taxes shall
occur until Taxes are determined for the fiscal year ending June 30, 2012.

6. Status of the Landlord’s Work.

6.1. Landlord’s Work, including the preparation of the 319 Required Parking
Spaces, will be substantially completed by December 1, 2009. December 1, 2009
will also be the date by which Landlord must have complied with the requirements
of Section 6.3 of the Original Lease.

6.2. With regard to Section 10.3 of the Original Lease, (a) acceptance of the
Premises will only occur upon December 1, 2009, and (b) Section 10.3(i)(a) will
be modified to commence as of the Rent Increase Date.

6.3. In connection with Section 10.1(a)(ii) of the Original Lease, Tenant waives
(a) any claim for reimbursement due to Landlord delays, and (b) any desire to
secure funding for its Tenant Costs through Tenant Improvement Rent.

6.4. This Second Amendment reflects the resolution of the parties as to any
claims under Section 17.4(b) of the Original Lease relating to the Schedule of
Deliveries.

6.5. In addition to any warranties from Landlord and any manufacturer assigned
to Tenant, Landlord hereby assigns to Tenant the benefit of all of the
warranties and guaranties of subcontractors and suppliers performing work or
supplying materials for Landlord’s Work.

7. Parking. Parking Rent will commence on (a) December 1, 2009 as to all
Required Parking Spaces then available to Tenant, and (b) as to all other
Required Parking Spaces as and when available to Tenant.

8. Self-Help. In the event that Landlord fails to perform any obligation
relating to the construction, preparation, renovation, operation, maintenance,
repair and/or replacement of any part of the Premises (generally, one or more
“Landlord Obligation”), including completion of the Landlord’s Work required to
achieve Final Approval, Tenant will have the following rights:

(a) In the absence of an emergency, Tenant may, after notice to Landlord of the
existence of a Landlord Obligation, and Landlord’s failure to perform such
Landlord Obligation within ten (10) days thereafter, undertake to perform such
Landlord Obligation and secure reimbursement from any Escrow Account maintained
by Landlord’s lender.

(b) In the event of an emergency, the notice period required by clause (a) above
will be reduced to such reasonable period commensurate with the immediacy of the
emergency, as determined in Tenant’s reasonable judgment.

(c) Landlord hereby consents to the above provisions and agrees to include such
reimbursement provisions in one or more agreements with each lender to which
Tenant has provided a subordination agreement.

 

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9. Miscellaneous. This Second Amendment may be executed in counterparts which
together shall be construed as a single document. The Lease, as amended by this
Second Amendment, is hereby ratified and confirmed and shall continue in full
force and effect.

[Signatures on following page]

 

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WITNESS OUR HANDS as of the day and year first above written.

 

ATTEST/WITNESS:     LANDLORD:     BEASON PROPERTIES, LLLP, a Maryland limited
liability limited partnership /s/ Steven Rosen     By:   BEASON GP LLC, General
Partner     By:   TIDE POINT FIDELCO LLC, Member       By:   /s/ Marc E. Berson
      Name:   Marc E. Berson       Title:   Managing Member

WITNESS or ATTEST:     TENANT:      

UNDER ARMOUR, INC.,

a Maryland corporation

  /s/ John P. Stanton     By:   /s/ J. Scott Plank   (SEAL)         Name:   J.
Scott Plank           Title:   Senior Vice-President  

For the purposes described in Section 21.16 of the Lease, as amended hereby.

WITNESS or ATTEST:     GUARANTOR:      

STRUEVER BROS. ECCLES & ROUSE, INC.

  /s/ Karen Morawski     By:   /s/ Carl. W. Struever   (SEAL)         Name:  
Carl W. Struever           Title:   President  

 

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CONSENT OF LENDERS

MANUFACTURERS AND TRADERS TRUST COMPANY, a New York banking corporation and THE
MICHELE FREIDUS 2006 IRREVOCABLE TRUST join in the foregoing Second Amendment to
Office Lease for the sole purpose of consenting thereto.

IN WITNESS WHEREOF, the undersigned have duly executed this Consent under seal
as of the 1st day of October, 2009.

 

ATTEST/WITNESS:     MANUFACTURERS AND TRADERS TRUST COMPANY       By:   /s/
Matthew G. Lind /s/ Shelly L. Hipsley     Name:   Matthew G. Lind       Title:  
Administrative Vice President ATTEST/WITNESS:     THE MICHELE FREIDUS 2006
IRREVOCABLE TRUST       By:   /s/ Marshall Freidus /s/ Steven Rosen     Name:  
Marshall Freidus       Title:   Trustee

 

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