Less than two months after the project groundbreaking, Kilroy Realty Corporation (NYSE: KRC) today said it has signed a 12-year lease with cloud storage and data-syncing leader Dropbox for 100% of the real estate investment trust's 182,000 square foot, William McDonough-designed office property currently under construction at 333 Brannan Street in San Francisco's South of Market (SOMA) district. 333 Brannan Street will be the second ground-up LEED Platinum office development project in San Francisco with the first being the company's 30-story tower leased to salesforce.com at 350 Mission Street.

"We are pleased to add another world class, dynamic technology leader to our portfolio," said John Kilroy, Jr., the company's chairman, president and chief executive officer. "The relationship we have built with Dropbox further demonstrates the success we've achieved in delivering the types of facilities and work environments that tenants want, which has created a virtuous cycle that continues to create additional opportunities for us."

The six-story brick and concrete building will feature large, efficient, open floor plates, abundant natural light, 100% outside air capability, and a large roof-top garden and roof deck. Among the cutting-edge sustainability attributes of the William McDonough + Partners design are onsite power-generation and a rainwater reclamation system expected to reduce energy usage by approximately 26% and water usage by 45% compared to a typical building of its size.

CBRE facilitated the transaction, led by Tim Kazul, Luke Ogelsby and Laurence Morgan representing the tenant and Phil Tippett, Cori English and Sherman Chan representing the landlord.

About Kilroy Realty Corporation. With more than 65 years of experience owning, developing, acquiring and managing commercial properties in West Coast real estate markets; publicly traded real estate investment trust Kilroy Realty Corporation (KRC), a member of the S&P MidCap 400 Index, is one of the region's premier landlords. The company provides physical work environments that can advance creativity and productivity to serve a roster of dynamic, innovation-driven tenants that includes technology, entertainment, digital media and health care companies. At September 30, 2013, the company's stabilized portfolio totaled 12.5 million square feet of office properties, all located in the coastal regions of greater Seattle, the San Francisco Bay Area, Los Angeles, Orange County, and San Diego. In addition, KRC has approximately 1.9 million square feet of new office development under construction with a total estimated investment of approximately $1.1 billion. More information is available at http://www.kilroyrealty.com.

Forward-Looking Statements. This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements are based on our current expectations, beliefs and assumptions, and are not guarantees of future performance. Forward-looking statements are inherently subject to uncertainties, risks, changes in circumstances, trends and factors that are difficult to predict, many of which are outside of our control. Accordingly, actual performance, results and events may vary materially from those indicated in forward-looking statements, and you should not rely on forward-looking statements as predictions of future performance, results or events. Numerous factors could cause actual future performance, results and events to differ materially from those indicated in forward-looking statements, including, among others, risks associated with: investment in real estate assets, which are illiquid; trends in the real estate industry; significant competition, which may decrease the occupancy and rental rates of properties; the ability to successfully complete acquisitions and dispositions on announced terms; the ability to successfully operate acquired properties; the availability of cash for distribution and debt service and exposure of risk of default under debt obligations; adverse changes to, or implementations of, applicable laws, regulations or legislation; and the ability to successfully complete development and redevelopment projects on schedule and within budgeted amounts. These factors are not exhaustive. For a discussion of additional factors that could materially adversely affect our business and financial performance, see the factors included under the caption "Risk Factors" in our annual report on Form 10-K for the year ended December 31, 2012 and our other filings with the Securities and Exchange Commission. All forward-looking statements are based on information that was available, and speak only, as of the date on which they are made. We assume no obligation to update any forward-looking statement made in this press release that becomes untrue because of subsequent events, new information or otherwise, except to the extent required in connection with ongoing requirements under U.S. securities laws.

Kilroy Realty Corporation
Tyler H. Rose
Executive Vice President and Chief Financial Officer
(310) 481-8484
or
Michelle Ngo
Senior Vice President and Treasurer
(310) 481-8581