CoreSite Realty Corporation Announces Closing of Offering of 7.25% Series A Cumulative Redeemable Preferred Stock

  CoreSite Realty Corporation Announces Closing of Offering of 7.25% Series A
  Cumulative Redeemable Preferred Stock

Business Wire

DENVER -- December 13, 2012

CoreSite Realty Corporation (NYSE: COR), an owner, developer and operator of
strategically located data centers in some of the leading communications hubs
in North America, today announced the closing of an underwritten public
offering of 4,600,000 shares of 7.25% Series A Cumulative Redeemable Preferred
Stock (the “Series A Preferred Stock”) at a price of $25.00 per share for net
proceeds of approximately $111 million, after deducting underwriting discounts
and commissions and expenses. The 4,600,000 shares of the Company’s Series A
Preferred Stock includes the underwriters’ exercise of their over-allotment
option on December 7, 2012 to purchase an additional 600,000 shares of the
Company’s Series A Preferred Stock. The Series A Preferred Stock is expected
to be admitted for trading on the New York Stock Exchange under the symbol
“CORprA” within 30 days of the date of closing.

The Company intends to contribute the net proceeds from this offering to its
operating partnership, CoreSite, L.P., which will subsequently use the net
proceeds received from the Company to temporarily repay borrowings under its
revolving credit facility, to repay the full amount of the mortgage loan
payable on its 12100 Sunrise Valley property and for general corporate
purposes, which could include the acquisition of additional properties or to
fund development and redevelopment opportunities. The offering is being made
pursuant to an effective shelf registration statement, prospectus and related
prospectus supplement filed by the Company with the Securities and Exchange
Commission.

Citigroup Global Markets Inc., Merrill Lynch, Pierce, Fenner & Smith
Incorporated and RBC Capital Markets, LLC are the joint book-running managers
for the offering. Credit Suisse Securities (USA) LLC and KeyBanc Capital
Markets Inc. are the co- managers for the offering.

A copy of the prospectus supplement and the accompanying prospectus relating
to these securities may be obtained, when available, by contacting Citigroup,
c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY
11717 (tel: 800-831-9146) or email: batprospectusdept@citi.com; Merrill Lynch,
Pierce, Fenner & Smith Incorporated, 222 Broadway, 7th Floor, New York, NY
10038, attention: Prospectus Department, or e-mail
dg.prospectus_requests@baml.com. Phone: 1-800-294-1322; RBC Capital Markets,
LLC, Attention: Prospectus Department, Three World Financial Center, 200 Vesey
Street, 8th floor, New York, New York 10281-8098, (866) 375-6829,
rbcnyfixedincomeprospectus@rbccm.com; Credit Suisse Securities (USA) LLC, One
Madison Avenue, New York, NY 10010, Attn: Prospectus Department. Phone:
1-800-221-1037; KeyBanc Capital Markets Inc., Phone: (866) 227-6479.

This press release is for informational purposes only and is not an offer to
sell or the solicitation of an offer to buy with respect to any securities in
any jurisdiction in which such offer, solicitation or sale would be unlawful.
The offering is not being made in any jurisdiction in which the making or
acceptance thereof would not be in compliance with the securities, blue sky or
other laws of such jurisdiction.

About CoreSite

CoreSite Realty Corporation (NYSE: COR) is an owner, developer and operator of
strategically located data centers in some of the leading communications hubs
in North America. These locations are among the largest and fastest growing
data center markets in the United States, including Los Angeles, the San
Francisco Bay and Northern Virginia areas, Chicago, Boston, New York City,
Miami, Denver, and Washington, DC. CoreSite works with a broad and growing
customer base of over 750 customers, including network and mobility services
providers, cloud service providers, digital content organizations, systems
integrators, managed service providers and enterprise customers of all sizes
with a variety of space, power and interconnection needs. As of September 30,
2012, CoreSite’s property portfolio included 14 operating data center
facilities and one development site, which collectively comprise over
2.1million net rentable square feet, or NRSF, of which approximately
1.2million NRSF represented existing data center space.

Forward Looking Statements

This press release contains forward-looking statements which are based on
current expectations, forecasts and assumptions that involve risks and
uncertainties that could cause actual outcomes and results to differ
materially. Such forward-looking statements include statements related to the
completion and timing of the offering, the intended use of proceeds from the
offering and the intended listing of the shares on the New York Stock
Exchange. These risks and uncertainties include, among others, the following:
the geographic concentration of CoreSite’s data centers in certain markets and
any adverse developments in local economic conditions or the demand for data
center space in these markets; fluctuations in interest rates and increased
operating costs; difficulties in identifying properties to acquire and
completing acquisitions; significant industry competition; CoreSite’s failure
to obtain necessary outside financing; CoreSite’s failure to qualify or
maintain its status as a REIT; financial market fluctuations; changes in real
estate and zoning laws and increases in real property tax rates; and other
factors affecting the real estate industry generally. For a further list and
description of such risks and uncertainties, see the reports and other filings
by the Company with the U.S. Securities and Exchange Commission, including the
Company’s Annual Report on Form 10-K for the year ended December 31, 2011. The
Company disclaims any intention or obligation to update or revise any
forward-looking statements, whether as a result of new information, future
events or otherwise.

Contact:

CoreSite Investor Relations Contact
+1 303.222.7276
InvestorRelations@CoreSite.com
or
CoreSite Media Contact
Jeannie Zaemes | CoreSite Marketing Senior Director
+1 720.446.2006 | +1 866.777.CORE
Jeannie.Zaemes@CoreSite.com