JOINDER TO CREDIT AGREEMENT

Exhibit 10.1

JOINDER TO CREDIT AGREEMENT

THIS JOINDER TO CREDIT AGREEMENT (this “Agreement”) is made this 28th day of June, 2013, by and among CORESITE, L.P., a Delaware limited partnership (“Parent Borrower”), the Subsidiary Borrowers party hereto, TORONTO DOMINION (TEXAS) LLC and KEYBANK NATIONAL ASSOCIATION, as administrative agent for the Lenders (the “Agent”).

R E C I T A L S

WHEREAS, the Parent Borrower and the Subsidiary Borrowers have entered into that certain Second Amended and Restated Credit Agreement dated as of January 3, 2013 (the “Credit Agreement”) with KeyBank National Association, as Administrative Agent (the “Agent”) on behalf of certain Lenders and the various Lenders party thereto (unless otherwise defined herein, capitalized terms defined in the Credit Agreement shall have the same meaning in this Agreement); and

WHEREAS, at the request of the Borrowers, Toronto Dominion (Texas) LLC (“TD”) has agreed to issue a Commitment and become a Lender under the Credit Agreement.

NOW, THEREFORE, in consideration of the recitals herein and mutual covenants and agreements contained herein, the parties hereto hereby agree as follows:

1.             TD hereby (a) acknowledges, agrees and confirms that, by its execution of this Agreement, it will be deemed to be a Lender for all purposes of the Credit Agreement and the other Loan Documents, issues its Commitment thereunder in the amount of $25,000,000.00, and shall have all of the rights and obligations of a Lender thereunder as if it had executed the Credit Agreement and the other Loan Documents; (b) agrees to be bound by, all of the terms, provisions and conditions contained in the Loan Documents applicable to a Lender; (c) confirms that it has received a copy of the Credit Agreement and the other Loan Documents, together with such other documents and information as it has deemed appropriate to make its own credit analysis and decision to become a Lender under the Credit Agreement; (d) confirms that all approvals and authorizations required to permit the execution, delivery, performance and consummation by TD of this Agreement, and the performance by TD as a Lender under the Credit Agreement, have been obtained; (e) agrees that it will, independently and without reliance upon the Agent or any other Lender and based on such documents and information as it shall deem appropriate at the time, continue to make its own credit decisions in taking or not taking action under the Credit Agreement or any other Loan Document; and (f) appoints and authorizes the Agent to take such action as agent on its behalf and to exercise such powers under the Credit Agreement and the other Loan Documents as are delegated to the Agent by the terms thereof together with such powers as are reasonably incidental thereto.  As of the date of this Agreement, TD shall be a party to the Credit Agreement and the other Loan Documents and shall have the rights and obligations of a Lender thereunder

2. The Credit Agreement is hereby deemed modified to reflect the increase in the Total Commitment evidenced hereby and the addition of TD as a Lender under the Credit

Agreement, and Schedule 1.1 attached hereto is hereby substituted in lieu of the pre-existing Schedule 1.1 to the Credit Agreement, to reflect the joinder of TD.

3. The Borrowers represent and warrant to the Lenders that after giving effect to this Agreement (a) the representations and warranties made by the Borrowers in the Loan Documents or otherwise made by or on behalf of the Borrowers in connection therewith or after the date thereof were true and correct in all material respects when made and remain true and correct in all material respects on the date the Total Commitment is increased, and (b) no event has occurred and is continuing which constitutes a Default or an Event of Default.

4. Each Borrower represents and warrants as follows:

(a) It has taken all necessary action to authorize the execution, delivery and performance of this Agreement.

(b) This Agreement has been duly executed and delivered by each Borrower and constitutes each Borrowers’ legal, valid and binding obligations, enforceable in accordance with its terms.

(c) No consent, approval, authorization or order of, or filing, registration or qualification with, any court or governmental authority or third party is required in connection with the execution, delivery or performance by Borrowers of this Agreement.

5. Except as expressly amended hereby, the remaining terms and conditions of the Credit Agreement shall continue in full force and effect.  All future references to the “Credit Agreement” shall be deemed to be references to the Credit Agreement, as amended by this Agreement.  It is intended that this Agreement be governed by the laws of the State of New York, including, without limitation, New York General Obligations Law Section 5-1401.

6. This Agreement shall be binding upon and inure to the benefit of the successors and assigns of the parties hereto.

7. For the purpose of facilitating the execution of this Agreement as herein provided and for other purposes, this Agreement may be executed simultaneously in any number of counterparts, each of which counterparts shall be deemed to be an original, and such counterparts shall constitute and be one and the same instrument.  Signatures delivered by facsimile or PDF shall have the same legal effect as originals.

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IN WITNESS WHEREOF, each of the undersigned have caused this Agreement to be executed by its duly authorized representatives as of the date first set forth above.

	PARENT BORROWER:
	CORESITE, L.P., a Delaware limited partnership, by its general partner, CoreSite Realty Corporation, a Maryland corporation
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel
		(SEAL)

[SIGNATURES CONTINUE ON FOLLOWING PAGE]

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	SUBSIDIARY BORROWERS:
	CORESITE REAL ESTATE 70 INNERBELT, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel
		(SEAL)
	CORESITE REAL ESTATE 000 X. XXXXXXX, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel
		(SEAL)
	CORESITE REAL ESTATE 2901 CORONADO, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel
		(SEAL)
	CORESITE REAL ESTATE 1656 XXXXXXXX, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel
		(SEAL)

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	CORESITE REAL ESTATE 427 X. XXXXXXX, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and
		General Counsel
		(SEAL)
	CORESITE CORONADO XXXXXXX, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and
		General Counsel
		(SEAL)
	CORESITE REAL ESTATE 0000 XX 00XX XXXXXX, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and
		General Counsel
		(SEAL)
	CORESITE ONE WILSHIRE, L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and
		General Counsel
		(SEAL)

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	CORESITE REAL ESTATE 00000 XXXXXXX XXXXXX XXXXX L.L.C., a Delaware limited liability company
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and
		General Counsel
		(SEAL)

[SIGNATURES CONTINUE ON FOLLOWING PAGE]

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			AGENT AND LENDER:
			KEYBANK NATIONAL ASSOCIATION, as Lender and as Agent
			By:	/s/ Xxxxxxx Xxxx
			Name:	Xxxxxxx Xxxx
			Title:	Vice President
			(SEAL)
Address:
KeyBank National Association 000 Xxxxxxxx Xxxxxx Xxxxxx, Xxxxxxxxxxxxx 00000
Attention:	Xxxxxxx X. Xxxx
Telephone:	000-000-0000
Facsimile:	000-000-0000

[SIGNATURES CONTINUE ON FOLLOWING PAGE]

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		LENDER:
		TORONTO DOMINION (TEXAS) LLC, as Lender
		By:	/s/ Xxxxxx Xxxxxx
		Name:	Xxxxxx Xxxxxx
		Title:	Authorized Signatory
		(SEAL)
Address: Toronto Dominion (Texas) LLC c/o TD Securities Royal Trust Tower, 25th Floor 00 Xxxx Xxxxxx Xxxx Xxxxxxx Xxxxxxx X0X 0X0 Attention: Xxxx Xxxxx
Telephone:	000-000-0000
Facsimile:	000-000-0000

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SCHEDULE 1.1

LENDERS AND COMMITMENTS

Name and Address				Revolving Credit Commitment			Revolving Credit Commitment Percentage		Alternative Currency Funding Commitment
KeyBank National Association 000 Xxxxxxxx Xxxxxx Xxxxxx, Xxxxxxxxxxxxx 00000 Attention:  Xxxxxxx X. Xxxx				$	65,000,000.00		17.10526315	%	$	6,842,105.26
Telephone:	000 000 0000
Facsimile:	000- 000-0000
LIBOR Lending Office Same as Above
Bank of America, N.A. 000 Xxxxxxxxxx Xxxxxx, 0xx Xxxxx XX0-000-00-00 Xxx Xxxxxxxxx, Xxxxxxxxxx 00000-0000				$	45,000,000.00		11.84210526	%	$	4,736,842.10
Attention:  Xxxxx X. Xxxxxxx
Telephone:	000-000-0000
Facsimile:	000-000-0000
LIBOR Lending Office Same as Above
CitiBank, N.A. 000 Xxxxxxxxx Xxxxxx, 00xx Xxxxx Xxx Xxxx, Xxx Xxxx 00000				$	45,000,000.00		11.84210526	%	$	4,736,842.10
Attention:  Xxxxxx Xxxxxxxx
Telephone:	000-000-0000
Facsimile:	000-000-0000
LIBOR Lending Office Same as Above

Name and Address				Revolving Credit Commitment			Revolving Credit Commitment Percentage		Alternative Currency Funding Commitment
Royal Bank of Canada New York Branch Three World Financial Center 000 Xxxxx Xxxxxx Xxx Xxxx, XX 00000-0000 Attn:  Manager, Loans Administration				$	65,000,000.00		17.10526315	%	$	6,842,105.26
Telephone:	000-000-0000
Facsimile:	000-000-000
LIBOR Lending Office Same as Above
Credit Suisse AG, Cayman Islands Branch Eleven Madison Avenue, 19th Floor Xxx Xxxx, XX 00000 Attention:  Xxxxxxx X’Xxxx, Vice President				$	35,000,000.00		9.210526315	%	$	3,684,210.53
Telephone:	000-000-0000
Facsimile:	000-000-0000
LIBOR Lending Office Same as Above
Regions Bank 0000 0xx Xxxxxx Xxxxx, 00xx Xxxxx Xxxxxxxxxx, Xxxxxxx 00000 Attention:  Xxxxx Xxxxxx				$	65,000,000.00		17.10526315	%	$	6,842,105.26
Telephone:	000 000 0000
Facsimile:	000 000 0000
LIBOR Lending Office Same as Above
CoBank, ACB 000 Xxxxx Xxxxxx Xxxxxx. Xxxxxxxxx Xxxxxxx, Xx. 00000				$	10,000,000.00		2.631578947	%	$	1,052,631.58

Name and Address				Revolving Credit Commitment			Revolving Credit Commitment Percentage		Alternative Currency Funding Commitment
Attention:  Xxxxxxxx Xxxxxx
Telephone:	000 000 0000
Facsimile:	000 000 0000
LIBOR Lending Office Same as above
Xxxxxxxxx Group, Inc. Xxxxxxxxx & Company, Inc. 000 Xxxxxxx Xxxxxx, 0xx Xxxxx Xxx Xxxx, XX 00000				$	25,000,000		6.578947368	%	$	2,631,578.95
Telephone:	000.000.0000
Facsimile:	646.786.5849
LIBOR Lending Office Same as above
Toronto Dominion (Texas) LLC c/o TD Securities Royal Trust Tower, 25th Floor 00 Xxxx Xxxxxx Xxxx Xxxxxxx Xxxxxxx X0X 0X0 Attention:  Xxxx Xxxxx				$	25,000,000		6.578947368	%	$	2,631,578.95
Telephone:	000-000-0000
Facsimile:	000-000-0000
LIBOR Lending Office Same as Above

Consent and Acknowledgment of Guarantor

The undersigned, as a Guarantor under that certain Second Amended and Restated Guaranty dated January 3, 2013 (the “Guaranty”) executed by the undersigned in favor of the Agent and the Lenders,  hereby consents to, and agrees to be bound by, this Agreement and hereby confirms and agrees that, notwithstanding this Agreement, the Guaranty and each other Loan Document to which it is a party are, and shall continue to be, in full force and effect and are hereby confirmed and ratified in all respects.

	GUARANTOR:
	CORESITE REALTY CORPORATION, a Maryland corporation
	By:	/s/ Xxxxx X. XxXxxxxxxx
	Name:	Xxxxx X. XxXxxxxxxx
	Title:	Senior Vice President, Legal, Secretary and General Counsel