Exhibit 99.1

Joint Filer Information

Date of Event Requiring Statement:	July 31, 2011
Issuer Name and Ticker or Trading Symbol:	CoreSite Realty Corp [ COR ]
Designated Filer:	Carlyle Realty IV GP, L.L.C.
Other Joint Filers:	Carlyle Realty IV, L.P. CoreSite CRP IV Holdings, LLC CRP IV AIV GP, L.L.C. CRP IV AIV GP, L.P. CRQP IV AIV, L.P. CoreSite CRP IV Holdings (VCOC I), LLC
Addresses:	The address of the principal business and principal office of each of Carlyle Realty IV GP, L.L.C., Carlyle Realty IV, L.P., CoreSite CRP IV Holdings, LLC, CRP IV AIV GP, L.L.C., CRP IV AIV GP, L.P., CRQP IV AIV, L.P. and CoreSite CRP IV Holdings (VCOC I), LLC is c/o The Carlyle Group, 1001 Pennsylvania Ave., N.W., Suite 220 South, Washington, DC 20004-2505.
Signatures:
Dated: August 2, 2011
	CARLYLE REALTY IV, GP, L.L.C. by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CARLYLE REALTY IV, L.P.
	by: Carlyle Realty IV, GP, L.L.C., its General Partner by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CORESITE CRP IV HOLDINGS, LLC
	by: Carlyle Realty IV, L.P., its Managing Member by: Carlyle Realty IV, GP, L.L.C., its General Partner by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CRP IV AIV GP, L.L.C.
	by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CRP IV AIV GP, L.P.
	by: CRP IV AIV GP, L.L.C., its General Partner by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CRQP IV AIV, L.P.
	by: CRP IV AIV GP, L.P., its General Partner by: CRP IV AIV GP, L.L.C., its General Partner by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director
	CoreSite CRP IV Holdings (VCOC I), LLC
	by: CRQP IV AIV, L.P., its Managing Member by: CRP IV AIV GP, L.P., its General Partner by: CRP IV AIV GP, L.L.C., its General Partner by: TC Group Investment Holdings, L.P., its Managing Member by: TCG Holdings II, L.P., its General Partner by: DBD Investors V, L.L.C., its General Partner by: DBD Investors V Holdings, L.L.C., its Managing Member
	by: /s/ R. Rainey Hoffman, attorney-in-fact Name: David M. Rubenstein Title: Managing Director