UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2004.2005.

For the Transition Period From                      to                     .

Commission file number 001-32336

DIGITAL REALTY TRUST, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (650) 233-3600(415) 738-6500

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15 (d)15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act.

Large-accelerated filer  ¨                 Accelerated filer  x                Non-accelerated filer  ¨

Indicate by check mark whether the registrant is an accelerated filera shell company (as defined in Rule 12b-2 of the Exchange Act)Act.).    Yes  ¨    No  x

The registrant completed its initial public offering on November 3, 2004. Consequently, the registrant is unable to determine the aggregate market value of its common stock asAs of June 30, 2004, which would have been the last business day of the registrant’s most recently completed second fiscal quarter. As of March 15, 2005, the aggregate market value of voting and non-votingthe registrant’s common stock held by non-affiliates of the registrant was approximately $303.5 million.$372.3 million based on the closing sale price as reported on the New York Stock Exchange.

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s Proxy Statement with respect to its May 6, 20052006 Annual Meeting of Stockholders to be filed not later than 120 days after the end of the registrant’s fiscal year are incorporated by reference into Part III hereof.

DIGITAL REALTY TRUST, INC.

FORM 10-K

FOR THE YEAR ENDED DECEMBER 31, 20042005

TABLE OF CONTENTS

PART 1

General

As used herein, the terms “we,” “our,” “us”“us,” “the company” and “our company” refer to Digital Realty Trust, Inc., a Maryland corporation, together with our consolidated subsidiaries, including Digital Realty Trust, L.P., a Maryland limited partnership of which we are the sole general partner and which we refer to as our operating partnership. We own, acquire, reposition and manage technology-related real estate. We target high quality,high-quality, strategically located properties containing applications and operations critical to the day-to-day operations of technology industry tenants.tenants and corporate data center users, including the information technology, or IT, departments of Fortune 1000 and financial services companies. Our tenant base is diversified within the technology industry and reflects a broad spectrum of regional, national and international tenants that are leaders in their respective areas. We operate as a real estate investment trust, or REIT, for federal income tax purposes.

As ofThrough our operating partnership, at December 31, 2004,2005 we owned 2443 properties. Our properties through our operating partnership. These properties are primarily located throughout the U.S., with one property locatedthree properties in London, England, andEurope. Our properties contain a total of approximately 5.78.1 million net rentable square feet.feet, excluding approximately 1.1 million square feet held for redevelopment. Our operations and acquisition activities are focused on a limited number of markets where technology industry tenants and corporate enterprise data center and technology tenantsusers are concentrated, including the Atlanta, Boston, Chicago, Dallas, Denver, London, Los Angeles, Miami, New York, Phoenix, Sacramento,Philadelphia, San Francisco and Silicon Valley metropolitan areas. As of December 31, 2004,2005, our portfolio, excluding space held for redevelopment, was approximately 88.4%93.9% leased at an average annualized rent per leased square foot of $19.93.$20.51. The property types of properties within our focus include:

ManyMost of our properties have extensive tenant improvements that have been installed at our tenants’ expense. Unlike traditional office and flex/research and development space, the location of and improvements to our facilities are generally essential to our tenants’ businesses, which we believe results in high occupancy levels, long lease terms and low tenant turnover. The tenant-installed improvements in our facilities are readily adaptable for use by similar tenants.

We also have approximately 1.1 million square feet available for redevelopment at December 31, 2005.

Our portfolio consists primarily ofincludes 21 properties contributed to us by Global Innovation Partners, LLC, or GI Partners, in connection with our initial public offering in November 2004. GI Partners is a private equity fund that was formed to pursue investment opportunities that intersect the real estate and technology industries. GI Partners was formed in February 2001 after a competitive six-month selection process conducted by the California Public EmployeeEmployees’ Retirement System, or CalPERS, the largest U.S. pension fund. Upon GI Partners’ selection, CalPERS provided a $500.0 million equity commitment to GI Partners to invest in technology-related real estate and technology operating businesses. In addition, CB Richard Ellis Investors, a subsidiary of CB Richard Ellis, or CBRE, the largest global real estate services firm, and members of GI Partners’ management, provided a commitment of $26.3 million.

Our senior management team, including our Executive Chairman, collectively has an average of over 23 years of experience in the technology or real estate industries, including experience as investors in, advisors to and founders of technology companies.

Our principal executive offices are located at 2730 Sand Hill Road,560 Mission Street, Suite 280, Menlo Park,2900, San Francisco, California 94025.94105. Our telephone number at that location is (650) 233-3600.(415) 738-6500. Our website is located at

www.digitalrealtytrust.com. The information found on, or otherwise accessible through, our website is not incorporated into, and does not form a part of, this annual report on Form 10-K or any other report or document we file with or furnish to the United States Securities and Exchange Commission.

In the final quarter of 2005 we renamed our properties based on the address of each building. This table shows the names of buildings at December 31, 2005 and the names of those buildings in previous filings.

Recent Developments

On December 22, 2005 we acquired 3 Corporate Place, a property located in the New York metropolitan area for approximately $14.7 million.

EffectiveOn December 8, 2005 we acquired 7500 & 7520 Metro Center Drive, a property located in Austin, Texas for approximately $13.5 million.

On November 26, 2004,29, 2005 we entered intoacquired 251 Exchange Place, a property located in Northern Virginia for approximately $12.9 million.

On November 10, 2005 we prepaid the outstanding balance of $25.6 million on our 600 West Seventh Street property mortgage. No prepayment fees were incurred as a result of this prepayment.

On November 9, 2005, we prepaid the outstanding balance of $22.0 million for the mezzanine loan on our 34551 Ardenwood Boulevard 1-4, 2334 Lundy Place and 2440 Marsh Lane properties. No prepayment fees were incurred as a result of this prepayment.

On November 1, 2005 we purchased Chemin de l’Epinglier 2, a data center in Geneva, Switzerland for approximately €10.1 million (approximately $12.2 million based on the exchange rate on November 1, 2005).

On October 4, 2005 we purchased 115 Second Avenue, a property in the Boston metropolitan area for approximately $14.3 million.

On October 4, 2005 we refinanced the mortgage related to our 200 Paul Avenue 1-4 property which resulted in a new loan for $81.0 million at an interest rate of 5.74% which matures on October 8, 2015. Also in October 2005, we terminated the interest rate swap agreements with Keybank National Associationrelated to this loan and Bank of America for approximately $140.3 million of our variable rate debt, of which $140.2 million was outstanding as of December 31, 2004. As a result, approximately 77.3% of our total indebtedness was subject to fixed interest rates as of December 31, 2004.

On December 21,2004, we purchased the Burbank Data Center, an 82,911 square foot, two-story data center and telecommunications property located in Burbank, California, for $16.6 million. The property was built in 1991 and features approximately 26,000 usable square feet of raised floor space. The property is 100% leased to Qwest Communications International, Inc. through 2011 at an annualized rentreceived cash of approximately $1.4 million or $17.06 per leased square foot. There are two five-year renewal options. Other than normal recurring capital expenditures, we have no plans with respect to renovation, improvement or redevelopment of the Burbank Data Center.

$0.4 million.

Subsequent Events

On January 14, 2005,February 27, 2006, we paid a partial fourth quarter dividend on our common stock and common units fordeclared the partial year beginning with our initial public offering on November 3, 2004 and ending on December 31, 2004 of $0.156318following distributions per common share and common unit. The dividend isthe Operating Partnership made an equivalent to an annual rate of $0.975distribution per common share and common unit.

As of December 31, 2004,On February 14, 2006 we ownedsigned an agreement to acquire a 75% tenancy-in-common interest in eBay Data Center, a 62,957 square foot data center located in Rancho Cordova, California. On January 21, 2005, we purchased the remaining 25% interest in this property for $4.1 million.

On January 24, 2005 we settled the foreign currency forward contract that we assumed from GI Partners related to the Camperdown House property located in the United KingdomToronto, Canada for a payment of approximately $2.5$16.0 million. On the same date we entered into a new foreign currency forward contract to hedge the foreign currency risk related to owning a property in the United Kingdom. On February 4, 2005 GI Partners reimbursed us for $1.9 million of such settlement since it was determined that the negative value associated with the forward contract was not otherwise factored into the determination of the number of units that were granted to GI Partners in exchange for its interests in Camperdown House.

On February 9, 2005, we completed the offering of 4.14 million shares of our 8.5% Series A Cumulative Redeemable Preferred Stock (liquidation preference $25.00 per share) for total net proceeds, after underwriting discounts and estimated expenses, of $99.3 million, including the proceeds from the exercise of the underwriters’ over-allotment option. We used the net proceeds from this offering to reduce borrowings under our unsecured credit facility, acquire two properties in March 2005 and for investment and general corporate purposes.

On February 14, 2005,2006 we declared a dividend on our series A preferred stock of $0.30694 per share for the period from February 9, 2005 through March 31, 2005, payable on March 31, 2005 to holders of record on March 15, 2005. The dividend is equivalent tosigned an annual rate of $2.125 per preferred share. On February 14, 2005, we also declared a dividend on our common stock and common units of $0.24375 per share, payable on March 31, 2005 to holders of record on March 15, 2005. The dividend is equivalent to an annual rate of $0.975 per common share and common unit.

On March 14, 2005, we purchased 833 Chestnut Street, a 15-story, 654,758 square foot building, including 107,563 square feet of vacant space in shell condition available for development, located in downtown

Philadelphia, Pennsylvania, for approximately $59.0 million. The property, originally constructed in 1927, was completely redeveloped in 2000. The renovation included extensive electrical and ventilation systems to accommodate data center users. The property is served by several major telecommunications networks, which makes it an attractive location for potential data center users. As of March 15, 2005, the property was 75.6% leased, including space available for development to 20 tenants, at an annualized rent of approximately $6.6 million or $13.97 per leased square foot. Excluding space available for development, the building was 90.5% occupied as of March 15, 2005.

On March 14, 2005, we entered into a purchase and sale agreement to acquire Printers’ Square, located in Chicago, Illinois. Printers’ Square is a five building complex comprising a total of approximately 161,550 net rentable square feet of commercial space. We expect the purchase price will be approximately $37.5 million. We made a deposit of $500,000 for the Printers’ Square property. The deposit is fully refundable if we terminate the purchase and sale agreement for any reason before April 25, 2005, the end of the due diligence period.

On March 15, 2005, we entered into a purchase and sale agreement to acquire Lakeside Technology Center located in Chicago, Illinois. Lakeside Technology Center is an 8-story re-developed historic building comprising a total of approximately 1,095,540 square feet, including approximately 820,540 net rentable square feet and approximately 275,000 square feet of space in shell condition held for redevelopment. We expect the purchase price will be approximately $142.6 million, which includes amounts payable to the seller in connection with its ongoing efforts to obtain a change in the real estate tax classification of the property. The seller can earn an additional contingent amount of up to $20.0 million by obtaining a change in the real estate tax classification prior to December 31, 2006. We made a deposit of $500,000 for the Lakeside Technology Center property. If we terminate the purchase and sale agreement before the end of the due diligence period for any reason other than a material default by the seller, the seller will be entitled to receive $250,000 of the deposit.

On March 17, 2005, we purchased MAPP Building, an 88,134 square foot property located in Minneapolis/St. Paul, Minnesota,Atlanta, Georgia for approximately $15.6 million. The property was built in 1947 and was fully re-developed in 1999 for the current tenant operations. MAPP Building contains a data center facility consisting of approximately 20,000 square feet of raised floor data center space. As of December 31, 2004, the property was 100% leased to the Midwest Independent Transmission System Operator, Inc., or MISO, through December 2013 at an annualized rent of approximately $1.3 million, or $15.20 per leased square foot. There is one five-year renewal option. Other than normal recurring capital expenditures, we have no plans with respect to renovation, improvement or redevelopment of the MAPP building.

In March 2005, we entered into an agreement to sublease approximately 9,674 square feet of office space at 560 Mission Street, San Francisco for a seven-year term. We will move our principal offices to this space on approximately June 1, 2005. The annual rent will be approximately $0.4$25.3 million.

On February 6, 2006 we purchased a property in Dublin, Ireland for €5.2 million ($6.3 million based on the rate of exchange on February 6, 2006) including $0.4 million in Stamp Duty Tax. We also paid an additional $0.8 million in Value Added Tax which we expect to recover in the first quarter of 2006.

On January 6, 2006 we acquired 4025 Midway Road in Carrollton, Texas, a suburb of Dallas for approximately $16.2 million.

Our Competitive Strengths

We believe we distinguish ourselves from other owners, acquirors and managers of technology-related real estate through our competitive strengths, which include:

Business and Growth Strategies

Our primary business objectives are to maximize sustainable long-term growth in earnings, funds from operations and cash flow per share and to maximize returns to our stockholders. Our business strategies to achieve these objectives are:

groups, technology tenants and real estate brokers who are dedicated to serving these tenants provide us with ongoing access to potential acquisitions and often enable us to avoid competitive bidding. Furthermore, the specialized nature of technology-related real estate makes it more difficult for traditional real estate investors to understand, which fosters reduced competition for acquisitions relative to other property types. We believe this dynamic creates an opportunity for us to obtain better risk-adjusted returns on our capital.

Competition

We compete with numerous regional developers, owners and operators of office and commercial real estate, many of which own properties similar to ours in the same submarkets in which our properties are located. If our competitors offer space at rental rates below current market rates, or below the rental rates we currently charge our tenants, we may lose potential tenants and we may be pressured to reduce our rental rates below those we currently charge in order to retain tenants when our tenants’ leases expire.

In addition, developers and operators may compete with us for acquisitions.

Regulation

General

Office properties in our submarkets are subject to various laws, ordinances and regulations, including regulations relating to common areas. We believe that each of our properties as of December 31, 20042005 has the necessary permits and approvals to operate its business.

Americans With Disabilities Act

Our properties must comply with Title III of the Americans with Disabilities Act of 1990, or ADA, to the extent that such properties are “public accommodations” as defined by the ADA. The ADA may require removal of structural barriers to access by persons with disabilities in certain public areas of our properties where such removal is readily achievable. We believe that our properties are in substantial compliance with the ADA and that we will not be required to make substantial capital expenditures to address the requirements of the ADA. However, noncompliance with the ADA could result in imposition of fines or an award of damages to private litigants. The obligation to make readily achievable accommodations is an ongoing one, and we will continue to assess our properties and to make alterations as appropriate in this respect.

Environmental Matters

Under various laws relating to the protection of the environment, a current or previous owner or operator of real estate may be liable for contamination resulting from the presence or discharge of hazardous or toxic substances at that property, and may be required to investigate and clean up such contamination at that property or emanating from that property. Such laws often impose liability without regard to whether the owner or operator knew of, or was responsible for, the presence of the contaminants, and the liability may be joint and several. Previous owners used some of our properties for industrial and retail purposes, so those properties may contain some level of environmental contamination. The presence of contamination or the failure to remediate contamination at our properties may expose us to third-party liability or materially adversely affect our ability to sell, lease or develop the real estate or to borrow using the real estate as collateral.

Some of the properties may contain asbestos-containing building materials. Environmental laws require that asbestos-containing building materials be properly managed and maintained, and may impose fines and penalties on building owners or operators for failure to comply with these requirements. These laws may also allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos-containing building materials.

In addition, some of our tenants, particularly those in the biotechnology and life sciences industry and those in the technology manufacturing industry, routinely handle hazardous substances and wastes as part of their operations at our properties. Environmental laws and regulations subject our tenants, and potentially us, to liability resulting from these activities or from previous industrial or retail uses of those properties. Environmental liabilities could also affect a tenant’s ability to make rental payments to us. We require our tenants to comply with these environmental laws and regulations and to indemnify us for any related liabilities.

Independent environmental consultants have conducted Phase I or similar environmental site assessments on all of the properties in our portfolio. Site assessments are intended to discover and evaluate information regarding

the environmental condition of the surveyed property and surrounding properties. These assessments do not generally include soil samplings, subsurface investigations or an asbestos survey. None of the recent site assessments revealed any past or present environmental liability that we believe would have a material adverse effect on our business, assets or results of operations. However, the assessments may have failed to reveal all environmental conditions, liabilities or compliance concerns. Material environmental conditions, liabilities or compliance concerns may have arisen after the review was completed or may arise in the future; and future laws, ordinances or regulations may impose material additional environmental liability.

Insurance

We carry comprehensive liability, fire, extended coverage, earthquake, business interruption and rental loss insurance covering all of the properties in our portfolio under a blanket policy. We select policy specifications and insured limits which we believe to be appropriate given the relative risk of loss, the cost of the coverage and industry practice and, in the opinion of our company’s management, the properties in our portfolio are currently adequately insured. We do not carry insurance for generally uninsured losses such as loss from riots, war or

nuclear reaction. In addition, we carry earthquake insurance on our properties in an amount and with deductibles which we believe are commercially reasonable. Certain of the properties in our portfolio are located in areas known to be seismically active. See “Risk Factors—Risks Related to Our Business and Operations—Potential losses may not be covered by insurance.”

Employees

As of December 31, 20042005 we had 2353 employees. None of these employees is represented by a labor union.

We have entered into an arrangement with a professional employer organization (PEO) pursuant to which the PEO provides personnel management services to us. The services are provided through a co-employment relationship between us and the PEO, under which all of our employees are treated as employed by both the PEO and us. The services and benefits provided by the PEO includeincluded payroll services, workers’ compensation insurance and certain employee benefits plan coverage. Our agreement with the PEO iswas terminable by either party upon 30 days’ prior written notice.

We terminated this agreement on January 1, 2006.

Offices

Our headquarters is located in Menlo Park, California. Based on the anticipated growth of our company, we intend to relocate our corporate headquarters to a larger facility in the near future. In addition, we may addSan Francisco. We have regional offices depending upon our future operational needs.in Boston, Chicago, Dallas, Los Angeles and New York.

Risk Factors

For purposes of this section, the term “stockholders” means the holders of shares of our common stock and of our series A preferred stock. Set forth below are the risks that we believe are material to our stockholders. You should carefully consider the following factors in evaluating our company, our properties and our business. The occurrence of any of the following risks might cause our stockholders to lose all or a part of their investment. Some statements in this report including statements in the following risk factors constitute forward-looking statements. Please refer to the section entitled “Forward-Looking Statements” on page 21.

at the end of Item 1A.

Risks Related to Our Business and Operations

Our properties depend upon the technology industry and the demand for technology-related real estate.

Our portfolio of properties consists primarily of technology-related real estate. A declinedecrease in the technology industrydemand for or the adoption of data center space, for corporate enterprises could lead to a decrease in the demand forInternet gateway facilities or other technology-related real estate which maycould have a greater adverse effect on our business and financial condition than if we owned a portfolio with a more diversified real estate portfolio.tenant base. We are susceptible to adverse developments in the corporate enterprise data center, Internet and data communications and broader technology industries (such as business layoffs or downsizing, industry

slowdowns, relocations of businesses, costs of complying with government regulations or increased regulation and other factors) and the technology-related real estate market (such as oversupply of or reduced demand for space). In addition, the rapid development of new technologies, orthe adoption of new industry standards or other factors could render many of our tenants’ current products and services obsolete or unmarketable and contribute to a downturn in their businesses, thereby increasing the likelihood of athat they default under their leases, or that they become insolvent or file for bankruptcy.

We depend on significant tenants, and many of our properties are single-tenant properties or are currently occupied by single tenants.

As of December 31, 2004,2005, the 15 largest tenants in our property portfolio represented approximately 66.1%61% of the total annualized rent generated by our properties. Our largest tenants by annualized rent are Savvis

Communications and Qwest Communications International, Inc.International. Savvis Communications leased 560,409approximately 1.1 million square feet of net rentable space as of December 31, 2004,2005, representing approximately 12.7%14.7% of the total annualized rent generated by our properties. Qwest Communications International Inc. leased 343,423approximately 655,000 square feet of net rentable space as of December 31, 2004,2005, representing approximately 9.3%11.2% of the total annualized rent generated by our properties. In addition, 1221 of our properties are occupied by single tenants. Our tenants may experience a downturn in their businesses or other factors which may weaken their financial condition and result in their failure to make timely rental payments or their default under their leases. In the event ofIf any tenant default,defaults or fails to make timely rent payments, we may experience delays in enforcing our rights as landlord and may incur substantial costs in protecting our investment.

The bankruptcy or insolvency of a major tenant may adversely affect the income produced by our properties.

If any tenant becomes a debtor in a case under the federal Bankruptcy Code, we cannot evict the tenant solely because of the bankruptcy. In addition, the bankruptcy court might authorize the tenant to reject and terminate its lease with us. Our claim against the tenant for unpaid, future rent would be subject to a statutory cap that might be substantially less than the remaining rent actually owed under the lease. In either case, our claim for unpaid rent would likely not be paid in full. At December 31, 2005 one tenant, VarTec Telecom, Inc. (VarTec) was in bankruptcy. As of December 31, 2004, two tenants,2005, VarTec Telecom, Inc., leasingleased approximately 143,882156,000 square feet of net rentable space across three separate properties and Universal Access Inc., leasingwas current on all of its rental obligations. In January 2006 VarTec notified us of its intention to file a motion to reject its lease of approximately 11,6808,600 square feet of net rentable space, were in bankruptcy. Both tenants are current on their rental obligations. Since we acquired our first building in January 2002, 14 tenants in our buildings leasing approximately 474,000 square feet of net rentable space concluded2323 Bryan Street property. The motion was granted by the bankruptcy proceedings. Of the 14 tenants, eight tenants leasing approximately 370,000 square feet of net rentable space paid rent to uscourt on an uninterrupted basisFebruary 21, 2006 and affirmed their leases. Of the approximately 104,000 square feet of net rentable space thatas such, this lease was rejected and terminated, we had re-leased approximately 21,000 square feet as of December 31, 2004.

effective February 28, 2006. We are currently considering options to pursue appropriate economic relief through the bankruptcy court.

Our revenue and cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, could be materially adversely affected if any of our significant tenants were to become bankrupt or insolvent, or suffer a downturn in its business, or fail to renew its lease or renew on terms less favorable to us than its current terms.

Our portfolio of properties depends upon local economic conditions and is geographically concentrated in certain locations.

As of December 31, 2004, ourOur properties wereare located only in the Amsterdam, Atlanta, Austin, Boston, Charlotte, Chicago, Dallas, Denver, Geneva, London, Los Angeles, Miami, Minneapolis/St. Paul, Northern Virginia, New York, Philadelphia, Phoenix, Sacramento, San Francisco and Silicon Valley metropolitan areas. We are dependentdepend upon the local economic conditions in these markets, including local real estate conditions. Many of these markets have experienced downturns during thewithin recent recession.years. Our operations may also be affected if too many competing properties are built in any of these markets. If there is a downturn in the economy in any of these markets, our operations and our revenue and cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, could be materially adversely affected. We cannot assure you that these markets will grow or will remain favorable to the technology industry.technology-related real estate.

In addition, our portfolio is geographically concentrated in the Boston, Dallas, Los Angeles, New York, San Francisco and Silicon Valleyfollowing metropolitan markets. These markets represented 9.7%, 19.2%, 10.3%, 6.9%, 10.9%, and 28.2%, respectively, of annualized rent as of December 31, 2004 of the properties in our portfolio. Thus, positive or

Any negative changes in real estate, technology or economic conditions in these markets in particular willcould negatively impact our overall performance.

We have owned our properties for a limited time.

As ofWe owned 43 properties at December 31, 2004, we owned 24 properties through our operating partnership.2005. These properties are primarily located throughout the U.S., with one property and three properties are located in London, England, andEurope. The properties contain a total of approximately 5.78.1 million net rentable square feet. As of December 31, 2004,feet, excluding 1.1 million square feet held for redevelopment. All the properties hadhave been under our management for less than threefour years, and 11we have owned 19 of the properties had been owned for less than one year.year at December 31, 2005. The properties may have

characteristics or deficiencies unknown to us that could affect such properties’their valuation or revenue potential. There can be no assuranceWe cannot assure you that the operating performance of the properties will not decline under our management.

We have space available for redevelopment that may be difficult to redevelop or successfully lease to tenants.

We have approximately 1.1 million square feet held for redevelopment at December 31, 2005 including two vacant buildings. Successful redevelopment of this space depends on numerous factors including success in engaging contractors, obtaining legal permits and availability of financing. In addition there can be no assurance that once completed we will be able to successfully lease to new or existing tenants. If we are not able to successfully redevelop this space, if redevelopment costs are higher than we currently estimate, or if we are not able to lease space that has been redeveloped, our revenue and operating results could be adversely effected.

We may have difficulty internalizingmanaging our assetgrowth.

We have significantly expanded the size of our company. For example, during 2005, we acquired 19 properties, including two properties outside the United States, and our number of employees increased from 23 to 53. The growth in our company may significantly strain our management, operational and financial resources and systems. In addition, as a public company, we are subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, the Sarbanes-Oxley Act of 2002, or the Sarbanes-Oxley Act, and the rules and regulations of the NYSE. The requirements of these rules and regulations have increased our accounting, legal and financial compliance costs and may strain our management and accounting functions.

A significant portion offinancial, legal and operational resources and systems. An inability to manage our growth effectively or the assetincreased strain on management and general and administrative functions of our predecessor were performed by GI Partners’ related-party asset manager, an affiliate of CB Richard Ellis Investors. Such affiliate also provided all ofresources and systems could result in deficiencies in our accountingdisclosure controls and procedures or our internal control over financial reporting services. Since the consummationand could adversely affect our results of our initial public offering, we have internalized our asset management function and have begun to internalize our accounting and financial reporting functions so that we can carry out the majority of our general and administrative functions directly. We cannot assure you that we will successfully internalize these functions on the anticipated timetable or without incurring unanticipated costs. We have entered into a transition services agreement with CB Richard Ellis Investors, pursuant to which CB Richard Ellis Investors will provide us with transitional accounting and other services for an interim period that we anticipate will last through the first fiscal reporting period of 2005. We currently retain affiliates of CB Richard Ellis as the property manager for seven of our properties.operations.

We have limited operating history as a REIT and as a public company.

We were formed in March 2004 and have limited operating history as a REIT and as a public company. We cannot assure you that our past experience will be sufficient to successfully operate our company as a REIT or as a public company. Failure to maintain REIT status would have an adverse effect on our cash available for distribution.

distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders.

Tax protection provisions on certain properties could limit our operating flexibility.

We have agreed with the third-party contributors who contributed the direct and indirect interests in the 200 Paul Avenue 1-4 and 1100 Space Park Drive properties to indemnify them against adverse tax consequences if we were to sell, convey, transfer or otherwise dispose of all or any portion of these interests, in a taxable transaction, in these properties. However, we can sell these properties in a taxable transaction if we pay the contributors cash in the amount of their tax liabilities arising from the transaction and tax payments. The 200 Paul Avenue 1-4 and 1100 Space Park Drive properties represented an aggregate of 14.4%10.6% of our portfolio’s annualized rent as of December 31, 2004.2005. These tax protection provisions apply for a period expiring on the earlier of November 3, 2013 and the date on which these contributors (or certain transferees) hold less than 25% of the units issued to them in connection with the contribution of these properties to our operating partnership. Although it may be in our stockholders’ best interest that we sell a property, it may be economically disadvantageous for us to do so because of these obligations. We have also agreed to make up to $20.0 million of debt available for these contributors to guarantee. We agreed to these provisions in order to assist these contributors in preserving their tax position after their contributions.

Potential losses may not be covered by insurance.

We carry comprehensive liability, fire, extended coverage, earthquake, business interruption and rental loss insurance covering all of the properties in our portfolio under various insurance policies. We select policy specifications and insured limits which we believe to be appropriate and adequate given the relative risk of loss, the cost of the coverage and industry practice. We do not carry insurance for generally uninsured losses such as loss from riots, war or nuclear reaction. Some of our policies, like those covering losses due to floods, are insured subject to limitations involving large deductibles or co-payments and policy limits which may not be sufficient to cover losses. A substantial portion of the properties we own are located in California, an area especially subject to earthquakes. Together, these properties represented approximately 50.5%42% of our portfolio’s annualized rent as of December 31, 2004.2005. While we carry earthquake insurance on our properties, the amount of our earthquake insurance coverage may not be sufficient to fully cover losses from earthquakes. In addition, we may discontinue

earthquake or other insurance on some or all of our properties in the future if the cost of premiums for any of these policies exceeds, in our judgment, the value of the coverage relative to the risk of loss.

In addition, many of our buildings contain extensive and highly valuable technology-related improvements. Under the terms of our leases, tenants generally retain title to such improvements and are obligated to maintain adequate insurance coverage applicable to such improvements and under most circumstances use their insurance proceeds to restore such improvements after a casualty. In the event of a casualty or other loss involving one of our buildings with extensive installed tenant improvements, our tenants may have the right to terminate their leases if we do not rebuild the base building within prescribed times. In such cases, the proceeds from the tenant’stenants’ insurance will not be available to us to restore the improvements, and our insurance coverage may be insufficient to replicate the technology-related improvements made by such tenant.

tenants. Furthermore, the terms of our mortgage indebtedness at certain of our properties may require us to pay insurance proceeds over to our lenders under certain circumstances, rather than use the proceeds to repair the property.

If we or one or more of our tenants experiences a loss which is uninsured or which exceeds policy limits, we could lose the capital invested in the damaged properties as well as the anticipated future cash flows from those

properties. In addition, if the damaged properties are subject to recourse indebtedness, we would continue to be liable for the indebtedness, even if these properties were irreparably damaged.

Payments on our debt reduce cash available for distribution and may expose us to the risk of default under our debt obligations.

Our total consolidated indebtedness as ofat December 31, 20042005 was approximately $519.5$749.1 million, and we may incur significant additional debt to finance future acquisition and development activities. OurWe also have an unsecured revolving credit facility which has a borrowing limit based upon a percentage of the value of theour unsecured properties included in the facility’s borrowing base. We estimate that approximately $53.9At December 31, 2005, $56.5 million of additional borrowingswas available under this facility were available to us as of December 31, 2004. Subsequent to the acquisitions of 833 Chestnut Street and MAPP Building, on March 17, 2005 there was approximately $26.0 million of the credit facility drawn and $71.9 million available for future borrowings.facility. In addition, under our contribution agreement with respect to the 200 Paul Avenue 1-4 and 1100 Space Park Drive properties, we have agreed to make available for guarantee up to $20.0 million of indebtedness and may enter into similar agreements in the future.

Payments of principal and interest on borrowings may leave us with insufficient cash resources to operate our properties, pay the dividends onto our series A preferred stockstockholders or makepay distributions onto our common stockstockholders necessary to maintain our REIT qualification. Our level of debt and the limitations imposed on us by our debt agreements could have significant adverse consequences, including the following:

If any one of these events were to occur, our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock, and our ability to satisfy our debt service obligations could be materially adversely affected. Furthermore, foreclosures could create taxable income without accompanying cash proceeds, a circumstance which could hinder our ability to meet the REIT distribution requirements imposed by the Internal Revenue Code (the Code).

Code.

We may be unable to identify and complete acquisitions and successfully operate acquired properties.

We continually evaluate the market of available properties and may acquire additional technology-related real estate when opportunities exist. Our ability to acquire properties on favorable terms and successfully operate them may be exposed to the following significant risks:

As of March 31, 2005, our operating partnership was under contract to acquire two properties: Lakeside Technology Center and Printers’ Square. The purchase of both of these properties is subject to numerous conditions, including the satisfactory conclusion by our operating partnership of its due diligence review of the properties during due diligence periods ending on April 13, 2005 and April 25, 2005, respectively. During the due diligence periods, our operating partnership has the right to terminate the purchase and sale agreements for these properties for any reason or for no reason.

If we cannot finance property acquisitions on favorable terms, or operate acquired properties to meet our financial expectations, our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock, and ability to satisfy our debt service obligations could be materially adversely affected.

We may be unable to source off-market deal flow in the future.

A key component of our growth strategy is to continue to acquire additional technology-related real estate. To date, more than half of our acquisitions were acquired before they were widely marketed by real estate brokers, or “off-market.” Properties that are acquired off-market are typically more attractive to us as a purchaser because of the absence of competitive bidding, which could potentially lead to higher prices. We obtain access to off-market deal flow from numerous sources. If we cannot obtain off-market deal flow in the future, our ability to locate and acquire additional properties at attractive prices could be adversely affected.

We face significant competition, which may decrease or prevent increases of the occupancy and rental rates of our properties.

We compete with numerous regional developers, owners and operators of real estate, many of which own properties similar to ours in the same submarkets in which our properties are located. If our competitors offer space at rental rates below current market rates, or below the rental rates we currently charge our tenants, we may lose potential tenants and we may be pressured to reduce our rental rates below those we currently charge in order to retain tenants when our tenants’ leases expire. As a result, our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock, and ability to satisfy our debt service obligations could be materially adversely affected.

We may be unable to renew leases, lease vacant space or re-lease space as leases expire.

As of December 31, 2004,2005, leases representing 1.2%2.9% of the square footage of the properties in our portfolio, excluding space held for redevelopment were scheduled to expire in 2005,2006, and an additional 11.6%6.1% of the net rentable square footage of the properties in our portfolioexcluding space held for redevelopment was available to be leased. We cannot assure you

that leases will be renewed or that our properties will be re-leased at net effective rental rates equal to or above the current average net effective rental rates. If the rental rates for our properties decrease, our existing tenants do not renew their leases or we do not re-lease a significant portion of our available space and space for which leases are scheduled to expire, our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock, and our ability to satisfy our debt service obligations could be materially adversely affected.

In addition at December 31, 2005 we held approximately 1.1 million square feet held for redevelopment. Successful redevelopment of this space depends on numerous factors including success in engaging contractors, obtaining environmental and legal permits and availability of financing. In addition, there can be no assurance that once we have redeveloped a space we will be able to successfully lease to new or existing tenants. If we are not able to successfully redevelop this space, if redevelopment costs are higher than we currently estimate, or if we are not able to lease space that has been redeveloped, our revenue and operating results could be adversely effected.

Our growth depends on external sources of capital which are outside of our control.

In order to maintain our qualification as a REIT, we are required under the Internal Revenue Code of 1986 as amended (the Code) to annually distribute at least 90% of our net taxable income, determined without regard to the dividends paid deduction and excluding any net capital gain. In addition, we will be subject to income tax at regular corporate rates to the extent that we distribute less than 100% of our net taxable income, including any net capital gains. Because of these distribution requirements, we may not be able to fund future capital needs, including any necessary acquisition financing, from operating cash flow. Consequently, we rely on third-party sources to fund our capital needs. We may not be able to obtain the financing on favorable terms or at all. Any additional debt we incur will increase our leverage. Our access to third-party sources of capital depends, in part, on:

If we cannot obtain capital from third-party sources, we may not be able to acquire or develop properties when strategic opportunities exist, satisfy our debt service obligations or make the cash distributions to our stockholders necessary to maintain our qualification as a REIT.

Our unsecured credit facility restricts our ability to engage in some business activities.

Our unsecured credit facility contains customary negative covenants and other financial and operating covenants that, among other things:

These restrictions could cause us to default on our unsecured credit facility or negatively affect our operations and our ability to makepay dividends to our preferred stockholders or distributions to our common stockholders.

Joint venture investments could be adversely affected by our lack of sole decision-making authority, our reliance on co-venturers’ financial condition and disputes between us and our co-venturers.

We may co-invest in the future with third parties through partnerships, joint ventures or other entities, acquiring non-controlling interests in or sharing responsibility for managing the affairs of a property, partnership, joint venture or other entity. In suchthat event, we would not be in a position to exercise sole decision-making authority regarding the property, partnership, joint venture or other entity. Investments in partnerships, joint ventures, or other entities may, under certain circumstances, involve risks not present werewhen a third party is not involved, including the possibility that partners or co-venturers might become bankrupt or fail to fund their share of required capital contributions. Partners or co-venturers may have economic or other business interests or goals which are inconsistent with our business interests or goals, and may be in a position to take actions contrary to our policies or objectives. Such investments may also have the potential risk oflead to impasses, on decisions, suchfor example, as to whether to sell a sale,property, because neither we nor the partner or co-venturer would have full control over the partnership or joint venture. Disputes between us and partners or co-venturers may result in litigation or arbitration that would increase our expenses and prevent our officers and/or directors from focusing their time and effort on our day-to-day business. Consequently, actions by or disputes with partners or co-venturers might result in subjectingmay subject properties owned by the partnership or joint venture to additional risk. In addition, we may in certain circumstances be liable for the actions of our third-party partners or co-venturers. We will seek to maintain sufficient controlEach of such entities to permit them to achievethese factors may result in returns on these investments being less than we expect or in losses and our business objectives.

financial and operating results may be adversely effected.

Our success depends on key personnel whose continued service is not guaranteed.

We depend on the efforts of key personnel, particularly Michael Foust, our Chief Executive Officer, A. William Stein, our Chief Financial Officer and Chief Investment Officer, and Scott Peterson, our Senior Vice President, Acquisitions. Among the reasons that theyAcquisitions and Christopher Crosby, our Senior Vice President, Sales and Technical Services. They are important to our success isfor many reasons, including that each has a national or regional reputation in our industry reputationand the investment community that attracts investors and business and investment opportunities and assists us in negotiations with investors, lenders, existing and potential tenants and industry personnel. If we lost their services, our business and investment opportunities and our relationships with lenders, existing and prospective tenants and industry personnel could diminish.

suffer. Many of our other senior executives also have strong technology and real estate industry reputations, which aid us in identifyingreputations. As a result, we have greater access to potential acquisitions and leasing and other opportunities, having opportunities broughtand are better able to us, and negotiatingnegotiate with tenants and build-to-suit prospects. While we believe that we could find replacements for alltenants. The loss of any of these key personnel would result in the loss of their servicesthese and other benefits and could materially and adversely affect our operations becauseresults of diminished relationships with lenders, existing and prospective tenants and industry personnel.operations.

Failure to hedge effectively against interest rate changes may adversely affect results of operations.

We seek to manage our exposure to interest rate volatility by using interest rate hedging arrangements, such as interest cap agreements and interest rate swap agreements. These agreements involve risks, such as the risk that counterparties may fail to honor their obligations under these arrangements, that these arrangements may not be effective in reducing our exposure to interest rate changes and that a court could rule that such an agreement is not legally enforceable. We have adopted aOur policy relatingis to the use of derivative financial instrumentsderivatives only to hedge interest rate risks related to our borrowings. This policy governs our use of derivative financial instruments to manage the interest rates on our variable rate borrowings. Our policy states that we willborrowings, not use derivatives for speculative or trading purposes, and intend only to enter into contracts only with major financial institutions based on their credit ratingratings and other factors, butfactors. However, we may choose to change these policiesthis policy in the future. We entered intoIncluding loans currently subject to interest rate swap agreements with Keybank National Association and Bank of America for $140.3 million of our variable rate debt with an effective date as of November 26, 2004. As a result,swaps, approximately 77.3%73% of our total indebtedness as of December 31, 20042005 was subject to fixed interest rates. Hedging may reduce the overall returns on our investments. Failure to hedge effectively against interest rate changes may materially adversely affect our results of operations.

Our properties may not be suitable for lease to traditional data center or technology office tenants without significant expenditures or renovations.

Because many of our properties contain extensive tenant improvements installed at our tenants’ expense, they may be better suited for a specific corporate enterprise data center user or technology industry tenant and could require modification in order for us to re-lease vacant space to another corporate enterprise data center user or technology industry tenant. Generally,In addition, our redevelopment space will generally require substantial improvement to be suitable for data center use. For the same reason, our properties also may not be suitable for lease to traditional office tenants without significant expenditures or renovations.

As a result, we may be required to invest significant amounts or offer significant discounts to tenants in order to lease or re-lease that space, either of which could adversely effect our financial and operating results.

Ownership of properties located outside of the United States subjects us to foreign currency and other risks which may adversely impact our ability to make distributions.

We own one propertyowned three properties located outside of the U.S. at December 31, 2005 and we have a right of first offer with respect to a secondanother property. In addition, we are currently considering, and will in the future consider, additional international acquisitions.

The ownership of properties located outside of the U.S. subjects us to foreign currency risk from potential fluctuations in exchange rates between foreign currencies and the U.S. dollar. We expect that our principal foreign currency exposuresexposure will be to the Pound Sterling (U.K.). As a result, changesBritish pound and the Euro. Changes in the relation of any such foreign currencythese currencies to U.S. dollars will affect our revenues and operating margins, may materially adversely impact our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock, and ability to satisfy our debt obligations.

obligations and ability to qualify as a REIT.

We intend to attempt to mitigate the risk of currency fluctuation by financing our properties in the local currency denominations, although we cannot assure you that we will be able to do so or that this will be effective. We may also engage in direct hedging activities to mitigate the risks of exchange rate fluctuations. If we do engage in foreign currency exchange rate hedging activities, any income recognized with respect to these hedges (as well as any foreign currency gain recognized with respect to changes in exchange rates) may not qualify under the 75% gross income test or the 95% gross income test that we must satisfy annually in order to qualify and maintain our status as a REIT.

Acquisition and ownership of foreign properties involve risks greater than those faced by us in the U.S.

Foreign real estate investments alsogenerally involve certain risks not generally associated with investments in the United States. TheseOur international acquisitions and operations are subject to a number of risks, include unexpected changesincluding:

Our inability to overcome these risks could adversely affect our foreign operations and could harm our business and results of adverse or confiscatory taxes, possible currency transfer restrictions, expropriation, difficulty in enforcing obligations in other countries and the burden of complying with a wide variety of foreign laws.operations.

Risks Related to the Real Estate Industry

Our performance and value are subject to risks associated with real estate assets and with the real estate industry.

Our ability to pay expected dividends to our preferred stockholders or pay distributions to our common and series A preferred stockholders depends on our ability to generate revenues in excess of expenses, scheduled principal payments on debt and capital expenditure requirements. Events and conditions generally applicable to owners and operators of real property that are beyond our control may decrease cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, and the value of our properties. These events and conditions include:

In addition, periods of economic slowdown or recession, rising interest rates or declining demand for real estate, or the public perception that any of these events may occur, could result in a general decline in rents or an increased incidence of defaults under existing leases, which would materially adversely affect our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock and ability to satisfy our debt service obligations.

Illiquidity of real estate investments could significantly impede our ability to respond to adverse changes in the performance of our properties and harm our financial condition.

Because real estate investments are relatively illiquid, our ability promptly to promptly sell one or more properties in our portfolio in response to adverse changes in thetheir performance of such properties may be limited, which may harm our financial condition. The real estate market is affected by many factors that are beyond our control, including:

We could incur significant costs related to government regulation and private litigation over environmental matters.

Under various laws relating to the protection of the environment, a current or previous owner or operator of real estate may be liable for contamination resulting from the presence or discharge of hazardous or toxic substances at that property, and may be required to investigate and clean up such contamination at that property

or emanating from that property. Such laws often impose liability without regard to whether the owner or operator knew of, or was responsible for, the presence of the contaminants, and the liability may be joint and several. Previous owners used some of our properties for industrial and retail purposes, so those properties may contain some level of environmental contamination. The presence of contamination or the failure to remediate contamination at our properties may expose us to third-party liability or materially adversely affect our ability to sell, lease or develop the real estate or to borrow using the real estate as collateral.

Some of the properties may contain asbestos-containing building materials. Environmental laws require that asbestos-containing building materials be properly managed and maintained, and may impose fines and penalties on building owners or operators for failure to comply with these requirements. These laws may also allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos-containing building materials.

In addition, some of our tenants, particularly those in the biotechnology and life sciences industry and those in the technology manufacturing industry, routinely handle hazardous substances and wastes as part of their operations at our properties. Environmental laws and regulations subject our tenants, and potentially us, to liability resulting from these activities or from previous industrial or retail uses of those properties. Environmental liabilities could also affect a tenant’s ability to make rental payments to us. We require our tenants to comply with these environmental laws and regulations and to indemnify us for any related liabilities.

Existing conditions at some of our properties may expose us to liability related to environmental matters.

Independent environmental consultants have conducted Phase I or similar environmental site assessments on all of the properties in our portfolio. Site assessments are intended to discover and evaluate information regarding the environmental condition of the surveyed property and surrounding properties. These assessments do not generally include soil samplings, subsurface investigations or an asbestos survey. None of the recent site assessments revealed any past or present environmental liability that we believe would have a material adverse effect on our business, assets or results of operations. However,survey and the assessments may have failedfail to reveal all environmental conditions, liabilities or compliance concerns. MaterialIn addition material environmental conditions, liabilities or compliance concerns may have arisenarise after the review wasthese reviews are completed or may arise in the future; and futurefuture. Future laws, ordinances or regulations may impose additional material additional environmental liability.

We cannot assure you that costs of future environmental compliance will not affect our ability to makepay dividends to our preferred stockholders or pay distributions to youour common stockholders or that such costs or other remedial measures will not have a material adverse effect on our business, assets or results of operations.

Our properties may contain or develop harmful mold or suffer from other air quality issues, which could lead to liability for adverse health effects and costs to remedy the problem.

When excessive moisture accumulates in buildings or on building materials, mold may grow, particularly if the moisture problem remains undiscovered or is not addressed over a period of time. Some molds may produce airborne toxins or irritants. Indoor air quality issues can also stem from inadequate ventilation, chemical contamination from indoor or outdoor sources and other biological contaminants such as pollen, viruses and bacteria. Indoor exposure to airborne toxins or irritants above certain levels can be alleged to cause a variety of adverse health effects and symptoms, including allergic or other reactions. As a result, the presence of significant mold or other airborne contaminants at any of our properties could require us to undertake a costly remediation program to contain or remove the mold or other airborne contaminants from the affected property or increase indoor ventilation. In addition, the presence of significant mold or other airborne contaminants could expose us to liability from our tenants, employees of our tenants and others if property damage or health concerns arise.

We may incur significant costs complying with the Americans with Disabilities Act and similar laws.

Under the Americans with Disabilities Act of 1990, or the ADA, all public accommodations must meet federal requirements related to access and use by disabled persons. Although we believe that as of December 31, 2004 the properties in our portfolio substantially complied with present requirements of the ADA, weWe have not conducted an audit or investigation of all of our properties to determine our compliance.compliance with the ADA. If one or more of the properties in our portfolio isdoes not in compliancecomply with the ADA, then we would be required to incur additional costs to bring the property into compliance. Additional federal, state and local laws also may require modifications to our properties, or restrict our ability to renovate our properties. We cannot predict the ultimate amount of the cost of compliance with the ADA or other legislation. If we incur substantial costs to comply with the ADA and any other similar legislation, our financial condition, results of operations, cash flow, cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock and our ability to satisfy our debt service obligations could be materially adversely affected.

We may incur significant costs complying with other regulations.

The properties in our portfolio are subject to various federal, state and local regulatory requirements,regulations, such as state and local fire and life safety requirements.regulations. If we fail to comply with these various requirements,regulations, we might incur governmentalmay have to pay fines or private damage awards. We believe that as of December 31, 2004 the properties in our portfolio materially complied with all applicable regulatory requirements. However,In addition, we do not know whether existing requirementsregulations will change or whether future requirementsregulations will require us to make significant unanticipated expenditures that will materially adversely impact our financial condition, results of operations, cash flow, cash available for distribution, theincluding cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, per share trading price of our common stock or series A preferred stock and our ability to satisfy our debt service obligations.

Risks Related to Our Organizational Structure

Conflicts of interest may exist or could arise in the future with holders of units in our operating partnership.

Conflicts of interest may exist or could arise in the future as a result of the relationships between us and our affiliates, on the one hand, and our operating partnership or any partner thereof, on the other. Our directors and officers have duties to our company and our stockholders under applicable Maryland law in connection with their management of our company. At the same time, we, as general partner, have fiduciary duties under Maryland law to our operating partnership and to the limited partners under Maryland law in connection with the management of our operating partnership. Our duties as general partner to our operating partnership and its partners may come into conflict with the duties of our directors and officers to our company and our stockholders. Under Maryland law, a general partner of a Maryland limited partnership owes its limited partners the duties of good faith, fairness and loyalty, unless the partnership agreement provides otherwise. The partnership agreement of our operating partnership provides that for so long as we own a controlling interest in our operating partnership, any conflict that cannot be resolved in a manner not adverse to either our stockholders or the limited partners will be resolved in favor of our stockholders.

Unless the relevant partnership agreement provides otherwise, Maryland law generally requires a general partner of a Maryland limited partnership to adhere to fiduciary duty standards under which it owes its limited partners the duties of good faith, fairness and loyalty.

Additionally, the partnership agreement expressly limits our liability by providing that we and our officers, directors, agents and employees, will not be liable or accountable to our operating partnership for losses sustained, liabilities incurred or benefits not derived if we, or such officer, director, agent or employee acted in good faith. In addition, our operating partnership is required to indemnify us, and our officers, directors, employees, agents and designees to the extent permitted by applicable law from and against any and all claims arising from operations of our operating partnership, unless it is established that (1) the act or omission was committed in bad faith, was fraudulent or was the result of active and deliberate dishonesty, (2) the indemnified party received an improper personal benefit in money, property or services or (3) in the case of a criminal proceeding, the indemnified person had reasonable cause to believe that the act or omission was unlawful.

The provisions of Maryland law that allow the fiduciary duties of a general partner to be modified by a partnership agreement have not been resolvedtested in a court of law, and we have not obtained an opinion of counsel covering the provisions set forth in the partnership agreement that purport to waive or restrict theour fiduciary duties that would be in effect were it not for the partnership agreement.

duties.

We are also subject to the following additional conflicts of interest with holders of units in our operating partnership:

We may pursue less vigorous enforcement of terms of contribution and othercertain agreements because of conflicts of interest with GI Partners and certain of our officers. GI Partners, and certain other contributors had ownership interestswhich owned a 40.2% interest in the properties and in the other assets and liabilities contributed to our operating partnership in our formation and have interests inat December 31, 2005, owns the propertiesproperty on which we have rightsa right of first offer. We, under the agreements relating to the contribution of such interests, have contractual rights to indemnification in the event of breaches of representations or warranties made by GI Partners and other contributors. In addition, GI Partners has entered into a non-competition agreement with us pursuant to which it agreed, among other things, not to engagecompete with us in certain business activities in competition with us.activities. Richard Magnuson, the Executive Chairman of our board of directors, is also, and will continue to be, the chief executive officer of the advisor to GI Partners. He as well asand certain

of our other senior executives have entered into employment agreements with us containing non-competition provisions. None of these contribution, option, right of first offer, employment and non-competition agreements was negotiated at arm’s-length. We may choose not to enforce, or to enforce less vigorously, our rights under these contribution, option, right of first offer, employment and non-competition agreements because of our desire to maintain our ongoing relationship with GI Partners and the other individuals involved.

Tax consequences upon sale or refinancing.Sales of properties and repayment of related indebtedness will have different effects onaffect holders of common units in our operating partnership than onand our stockholders.stockholders differently. The parties who contributed the 200 Paul Avenue 1-4 and 1100 Space Park Drive properties to our operating partnership would incur adverse tax consequences upon the sale of these properties and on the repayment of related debt which differ from the tax consequences to us and our stockholders. Consequently, these holders of common units in our operating partnership including John O. Wilson, our Executive Vice President, Technology Infrastructure, may have different objectives regarding the appropriate pricing and timing of any such sale or repayment of debt. While we have exclusive authority under the limited partnership agreement of our operating partnership to determine when to refinance or repay debt or whether, when, and on what terms to sell a property, any such decision would require the approval of our board of directors. Certain of our directors and executive officers could exercise their influence in a manner inconsistent with the interests of some, or a majority, of our stockholders, including in a manner which could prevent completion of a sale of a property or the repayment of indebtedness.

Our charter and Maryland law contain provisions that may delay, defer or prevent a change of control transaction.

Our charter and the articles supplementary with respect to the series A preferred stock contain 9.8% ownership limits. Our charter, and the articles supplementary with respect to the series A preferred stock, subject to certain exceptions, authorizeauthorizes our directors to take such actions as are necessary and desirable to preserve our qualification as a REIT and limitsto limit any person to actual or constructive ownership of no more than 9.8% (by value or by number of shares, whichever is more restrictive) of the outstanding shares of our common stock, 9.8% (by value or by number of shares, whichever is more restrictive) of the outstanding shares of ourany series Aof preferred stock and 9.8% of the value of our outstanding capital stock. Our board of directors, in its sole discretion, may exempt a proposed transferee from the ownership limit. Our board of directors granted such an exemption with respect to the ownership of our series A preferred stock to one of the initial investors. However, our board of directors may not grant an exemption from the ownership limit to any proposed transferee whose direct or indirect ownership of more than 9.8% of the outstanding shares of our common stock, more than of 9.8% of the outstanding shares of ourany series Aof preferred stock or more than 9.8% of the value of our outstanding capital stock could jeopardize our status as a REIT. These restrictions on transferability and ownership will not apply if our

board of directors determines that it is no longer in our best interests to attempt to qualify, or to continue to qualify, as a REIT. The ownership limit may delay, defer or prevent a transaction or a change of control that might be in the best interest of our series Acommon or preferred stockholders.

We could increase the number of authorized shares of stock and issue stock without stockholder approval.Our charter authorizes our board of directors, without stockholder approval, to increase the aggregate number of authorized shares of stock or the number of authorized shares of stock of any class or series, to issue authorized but unissued shares of our common stock or preferred stock and, subject to series Athe voting rights of holders of preferred stockholder voting rights,stock, to classify or reclassify any unissued shares of our common stock or preferred stock and to set the preferences, rights and other terms of such classified or unclassifiedreclassified shares. Although our board of directors has no such intention at the present time, it could establish a series of preferred stock that could, depending on the terms of such series, delay, defer or prevent a transaction or a change of control that might be in the best interest of our common or preferred stockholders.

Certain provisions of Maryland law could inhibit changes in control.Certain provisions of the Maryland General Corporation Law, or MGCL may have the effect of inhibitingimpeding a third party from making a proposal to acquire us or of impeding a change of control under circumstances that otherwise could be in the best interests of our common or preferred stockholders, including:

or more of the voting power of our shares or an affiliate or associate of ours who, at any time within the two-year period prior to the date in question, was the beneficial owner of 10% or more of our then outstanding voting shares) or an affiliate thereof for five years after the most recent date on which the stockholder becomes an interested stockholder, and thereafter imposes special appraisal rights and special stockholder voting requirements on these combinations; and

We have opted out of these provisions of the MGCL, in the case of the business combination provisions of the MGCL by resolution of our board of directors, and in the case of the control share provisions of the MGCL pursuant to a provision in our bylaws. However, our board of directors may by resolution elect to opt in to the business combination provisions of the MGCL and we may, by amendment to our bylaws, opt in to the control share provisions of the MGCL in the future.

The provisions of our charter on removal of directors and the advance notice provisions of the bylaws could delay, defer or prevent a transaction or a change of control of our company that might be in the best interest of our common or preferred stockholders. Likewise, if our company’s board of directors were to opt in to the business combination provisions of the MGCL or the provisions of Title 3, Subtitle 8 of the MGCL, or if the provision in our bylaws opting out of the control share acquisition provisions of the MGCL were rescinded, these provisions of the MGCL could have similar anti-takeover effects. Further, our partnership agreement provides that our company may not engage in any merger, consolidation or other combination with or into another person, sale of all or substantially all of our assets or any reclassification or any recapitalization or change in outstanding shares of our common stock, unless in connection with such transaction we obtain the consent of the holders of at least 35% of our operating partnership’s common and long-term incentive units (including units held by us), and certain other conditions are met.

Our board of directors may change our investment and financing policies without stockholder approval and we may become more highly leveraged, which may increase our risk of default under our debt obligations.

Our board of directors adopted a policy of limiting our indebtedness to 60% of our total market capitalization. Our total market capitalization is defined as the sum of the market value of our outstanding common stock (which may decrease, thereby increasing our debt to total market capitalization ratio), excluding options issued under our incentive award plan, plus the aggregate value of the units not held by us, plus the liquidation preference of outstanding preferred stock, plus the book value of our total consolidated indebtedness. However, our organizational documents do not limit the amount or percentage of indebtedness, funded or otherwise, that we may incur. Our board of directors may alter or eliminate our current policy on borrowing at any time without stockholder approval. If this policy changed, we could become more highly leveraged which could result in an increase in our debt service and which could materially adversely affect our cash flow and our ability to make distributions.distributions, including cash available to pay dividends to our preferred stockholders or pay distribution to our common stockholders. Higher leverage also increases the risk of default on our obligations.

Our rights and the rights of our stockholders to take action against our directors and officers are limited.

Maryland law provides that a director or officer hasour directors and officers have no liability in that capacitytheir capacities as directors or officers if he or she performs his or herthey perform their duties in good faith, in a manner he or shethey reasonably believesbelieve to be in our best interests and with the care that an ordinarily prudent person in a like position would use under similar circumstances. As

permitted by the MGCL, our charter limits the liability of our directors and officers to us and our stockholders for money damages, except for liability resulting from:

In addition, our charter authorizes us to obligate our company, and our bylaws require us, to indemnify our directors and officers for actions taken by them in those capacities to the maximum extent permitted by Maryland law.law and we have entered in indemnification agreements with our officers and directors. As a result, we and our stockholders may have more limited rights against our directors and officers than might otherwise exist under common law. Accordingly, in the event that actions taken in good faith by any of our directors or officers impede the performance of our company, your ability to recover damages from suchthat director or officer will be limited.

Risks Related to Our Status as a REIT

Failure to qualify as a REIT would have significant adverse consequences to us and the value of our stock.

We believe we have operated and intend to continue operating in a manner that we believe will allow us to qualify as a REIT for federal income tax purposes under the Code. We have not requested and do not plan to request a ruling from the IRS that we qualify as a REIT, and the statements in this report are not binding on the IRS or any court.REIT. If we lose our REIT status, we will face serious tax consequences that would substantially reduce our cash available for distribution, including cash available to pay dividends to our preferred stockholders or pay distributions to our common stockholders, for each of the years involved because:

In addition, if we fail to qualify as a REIT, we will not be required to make distributions to stockholders. As a result of all these factors, our failure to qualify as a REIT also could impair our ability to expand our business and raise capital, and would materially adversely affect the value of our capital stock.

Qualification as a REIT involves the application of highly technical and complex Code provisions for which there are only limited judicial and administrative interpretations. The complexity of these provisions and of the applicable Treasury regulationsRegulations that have been promulgated under the Code is greater in the case of a REIT that, like us, holds its assets through a partnership. The determination of various factual matters and circumstances not entirely within our control may affect ourOur ability to qualify as a REIT.REIT may be affected by facts and circumstances that are not entirely within our control. In order to qualify as a REIT, we must satisfy a number of requirements, including requirements regarding the composition of our assets and a requirement that at least 95% of our gross income in any year must be derived from qualifying sources, such as “rents from real property.” Also, we must make distributions to stockholders aggregating annually at least 90% of our net taxable income, excluding net capital gains. In addition, legislation, new regulations, administrative interpretations or court decisions may materially adversely affect our investors, our ability to qualify as a REIT for federal income tax purposes or the desirability of an investment in a REIT relative to other investments.

Even if we qualify as a REIT for federal income tax purposes, we may be subject to some federal, state and local taxes on our income or property and, in certain cases, a 100% penalty tax, in the event we sell property as a dealer. In addition, our domestic taxable REIT subsidiaries willsubsidiary could be subject to Federal and state taxes and our foreign properties and companies are subject to tax as regular corporations in the jurisdictions in which they operate including, in the case of the entity holding Camperdown House, the United Kingdom.and are located.

To maintain our REIT status, we may be forced to borrow funds on a short-term basis during unfavorable market conditions.

To qualify as a REIT, we generally must distribute to our stockholders at least 90% of our net taxable income each year, excluding capital gains, and we will be subject to regular corporate income taxes to the extent that we distribute less than 100% of our net taxable income each year. In addition, we will be subject to a 4% nondeductible excise tax on the amount, if any, by which distributions paid by us in any calendar year are less than the sum of 85% of our ordinary income, 95% of our capital gain net income and 100% of our undistributed income from prior years. In order to maintain our REIT status and avoid the payment of income and excise taxes, we may need to borrow funds on a short-term basis to meet the REIT distribution requirements even if the then prevailing market conditions are not favorable for these borrowings. These short-term borrowing needs could result from differences in timing between the actual receipt of cash and inclusion of income for federal income tax purposes, or the effect of non-deductible capital expenditures, the creation of reserves or required debt or amortization payments.

The ability of our board of directors to revoke our REIT election without stockholder approval may cause adverse consequences to our stockholders.

Our charter provides that our board of directors may revoke or otherwise terminate our REIT election, without the approval of our stockholders, if it determines that it is no longer in our best interests to continue to qualify as a REIT. If we cease to qualify as a REIT, we would become subject to U.S. federal income tax on our taxable income and we would no longer be required to distribute most of our taxable income to our stockholders, which may have adverse consequences on the total return to our common or preferred stockholders.

Forward-Looking Statements

We make statements in this report that are forward-looking statements within the meaning of the federal securities laws. In particular, statements pertaining to our capital resources, portfolio performance and results of operations contain forward-looking statements. Likewise, all of our statements regarding anticipated market conditions, demographics and results of operations are forward-looking statements. You can identify forward-looking statements by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “seeks,” “approximately,” “intends,” “plans,” “pro forma,” “estimates” or “anticipates” or the negative of these words and phrases or similar words or phrases which are predictions of or indicate future events or trends and which do not relate solely to historical matters. You can also identify forward looking statements by discussions of strategy, plans or intentions.

Forward-looking statements involve numerous risks and uncertainties and you should not rely on them as predictions of future events. Forward-looking statements depend on assumptions, data or methods which may be incorrect or imprecise and we may not be able to realize them. We do not guarantee that the transactions and events described will happen as described (or that they will happen at all). The following factors, among others,

could cause actual results and future events to differ materially from those set forth or contemplated in the forward-looking statements:

While forward-looking statements reflect our good faith beliefs, they are not guaranties of future performance. We disclaim any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors, of new information, data or methods, future events or other changes. For a further discussion of these and other factors that could impact our future results, performance or transactions, see the section above entitled “—Risk Factors.”

None.

Our Portfolio

As of December 31, 2004,2005, we owned 2443 properties through our operating partnership. These properties are primarily located throughout the U.S., with one propertythree properties located in London, England,Europe, and contain a total of approximately 5.78.1 million net rentable square feet.feet excluding 1.1 million square feet held for redevelopment. The following table presents an overview of our portfolio of properties, based on information as of December 31, 2004.2005.

Property(1)		Metropolitan Area		Percent Ownership			Year built/renovated		Net Rentable Square Feet Excluding Redevelopment Space(2)		Redevelopment Space(3)		Percent leased(4)			Annualized Rent ($000)(5)			Annualized Rent per Leased Square Foot ($000)(6)
Internet Gateways
350 East Cermak Road		Chicago		100.0	%		1912-1929/2000		870,183		263,208		92.2	%		$	18,640		$	23.23
200 Paul Avenue 1-4		San Francisco		100.0			1955/1999 & 2001		494,608		37,630		95.8				12,881			27.18
2323 Bryan Street		Dallas		100.0			1983		457,217		19,890		82.0				8,455			22.55
600 West Seventh Street		Los Angeles		100.0			1922/1999		430,759		59,319		90.8				7,858			20.09
600-780 S. Federal		Chicago		100.0			1912/1982		161,547		—		84.1				4,405			32.42
6 Braham Street(7)		London, England		100.0			1983/1999		63,233		—		100.0				3,816			60.35
1100 Space Park Drive		Silicon Valley		100.0			2001		82,409		85,542		94.9				3,598			46.01
36 NE 2nd Street		Miami		100.0			1927/1999		162,140		—		81.2				3,232			24.55
731 East Trade Street		Charlotte		100.0			1999/2000/2001		40,879		—		100.0				1,007			24.63
113 North Myers		Charlotte		100.0			1999/2000/2001		18,717		10,501		100.0				444			23.72
125 North Myers		Charlotte		100.0			1999/2000/2001		12,151		13,242		85.8				229			21.97
									2,793,843		489,332		90.2				64,565			25.61
Data Centers
833 Chestnut Street		Philadelphia		100.0			1927/1998		535,098		119,660		91.5				7,222			14.75
300 Boulevard East		New York		100.0			1989/2000		311,950		—		87.4				6,867			25.19
2045 & 2055 LaFayette Street		Silicon Valley		100.0			2000		300,000		—		100.0				5,940			19.80
150 South First Street		Silicon Valley		100.0			1987/1999		187,334		—		98.5				4,750			25.74
11830 Webb Chapel Road		Dallas		100.0			1966/2000		365,648		—		93.3				4,689			13.74
2334 Lundy Place		Silicon Valley		100.0			1982-83/2001		130,752		—		100.0				3,932			30.07
2401 Walsh Street		Silicon Valley		100.0			1973/2000		167,932		—		100.0				3,028			18.03
200 North Nash Street		Los Angeles		100.0			1975/1998-99		113,606		—		100.0				2,048			18.03
2403 Walsh Street		Silicon Valley		100.0			1972/1999		103,940		—		100.0				1,874			18.03
Paul van Vlissingenstraat 16(7)(12)		Amsterdam, Netherlands		100.0			1988/2000		112,472		—		62.0				1,658			23.78
4700 Old Ironsides Drive		Silicon Valley		100.0			1977/2000		90,139		—		100.0				1,625			18.03
8534 Concord Center Drive		Denver		100.0			2001		82,229		—		100.0				1,521			18.50
3065 Gold Camp Drive		Sacramento		100.0			1983/2000		62,957		—		100.0				1,487			23.62
3015 Winona Avenue		Los Angeles		100.0			1991		82,911		—		100.0				1,414			17.05
251 Exchange Place		Northern Virginia		100.0			1984		70,982		—		100.0				1,374			19.36
2440 Marsh Lane		Dallas		100.0			1999		135,250		—		100.0				1,353			10.00
1125 Energy Park Drive		Minneapolis/St. Paul		100.0			1947/1999		88,134		—		100.0				1,340			15.20
3300 East Birch Street		Los Angeles		100.0			1981/2000		68,807		—		100.0				1,228			17.85
Chemin de l’Epinglier 2(7)		Geneva, Switzerland		100.0			1984/2003		59,190		—		100.0				1,176			19.87
375 Riverside Parkway		Atlanta		100.0			1998		126,300		123,891		100.0				1,138			9.01
7500 & 7520 Metro Center Drive		Austin		100.0			2000		45,000		74,962		100.0				551			12.24
3 Corporate Place		New York		100.0			1974/1993-1996		—		283,124		—				—			—
115 Second Avenue		Boston		100.0			1960/2001		12,500		55,569						—			—
									3,253,131		657,206		94.9				56,215			18.22

Property(1)		Metropolitan Area		Percent Ownership			Year built/renovated			Net Rentable Square Feet Excluding Redevelopment Space(2)		Redevelopment Space(3)		Percent leased(4)			Annualized Rent ($000)(5)			Annualized Rent per Leased Square Foot ($000)(6)
Technology Manufacturing
34551 Ardenwood Boulevard 1-4		Silicon Valley		100.0	%		1985-86			307,657		—		100.0	%		$	7,941		$	25.81
47700 Kato Road & 1055 Page Avenue		Silicon Valley		100.0			1991 & 1997	(8)		183,050		—		100.0				3,472			18.97
2010 East Centennial Circle(9)		Phoenix		100.0			2002			113,405		—		100.0				2,549			22.48
										604,112		—		100.0				13,962			23.11
Technology Office
100 & 200 Quannapowitt Parkway		Boston		100.0			1957 & 1999	(10)		386,956		—		100.0				5,989			15.48
100 Technology Center Drive		Boston		100.0			1989/2001			197,000		—		100.0				3,743			19.00
4055 Valley View Lane		Dallas		100.0			1999			240,065		—		94.3				3,435			15.17
7979 East Tufts Avenue		Denver		98.0	(11)		1982			366,184		—		89.0				3,286			10.08
4849 Alpha Road		Dallas		100.0			1999			125,538		—		100.0				2,263			18.03
4650 Old Ironsides Drive		Silicon Valley		100.0			1977/2000			84,383		—		100.0				1,521			18.02
										1,400,126		—		96.1				20,237			15.03
Portfolio Total/Weighted Average										8,051,212		1,146,538		93.9	%		$	154,979		$	20.51

(3)

Redevelopment space is unoccupied space that requires significant capital investment in order to develop data center facilities that are ready for use. Most often this is shell space. However, in certain circumstances this may include partially built data center space that was not completed by previous ownership and requires a large capital investment in order to build out the space.

(4)

Excludes space held for redevelopment. Includes unoccupied space for which we are receiving rent and excludes space for which leases had commenced as of December 31, 2005 but for which we are not receiving rent. We completed a review of space held for redevelopment in the quarter ended September 30, 2005 and have not amended filings for earlier periods. This will cause occupancy statistics for these periods to not be comparable to the December 31, 2005 occupancy statistics presented in this filing.

(5)

Annualized rent represents the annualized monthly contractual rent under existing leases as of December 31, 2004.2005 multiplied by twelve. This amount reflects total base rent before any one-time or non-recurring rent abatements but after annually recurring rent credits and is shown on a net basis; thus, for any tenant under a partial gross lease, the expense stop, or under a full gross lease, the current year operating expenses (which may be estimates as of such date), are subtracted from gross rent.

(4)(6)

Annualized rent per leased square foot represents annualized rent as computed above, divided by the total square footage under lease as of the same date.

(5)(7)

Rental amounts for Camperdown House6 Braham Street were calculated based on the exchange rate in effect on December 31, 20042005 of $1.8519$1.72 per £1.00.£1.00 and rental amounts for Paul van Vlissingenstraat 16 and Chemin de l’Epinglier 2 were calculated based on the exchange rate in effect on December 31, 2005 of $1.18 per € 1.00. Chemin de l’Epinglier 2 is subject to a ground lease which expires in July 2074.

(6)(8)

As of December 31, 2004, we owned a 75% tenancy-in-common interest in this property. On January 21, 2005, we purchased the remaining 25% interest in this property.

(7)	This property consists of two buildings: 1055 Page Avenue was built in 1991 and 47700 Kato Road was built in 1997.

(8)(9)

We own the subsidiary that is party to a ground sublease coveringfor this property. The term of the ground sublease expires on December 31, 2082.

(9)(10)

This property consists of two buildings: 100 Quannapowitt was built in 1999 and 200 Quannapowitt was built in 1957 and has subsequently been renovated.

(10)(11)

We indirectly own a 98% interest in a subsidiary that holds the fee simple interest in this property. An unrelated third party holds the remaining 2% interest in this subsidiary.

(11)(12)

We are party to a ground sublease for this property. The building includes approximately 55,000 net rentable square feetterm of support space such as rooftop areas, generator pads and electrical room space for which rent is currently being charged to certain tenants.the ground sublease expires on April 2054.

Tenant Diversification

As of December 31, 20042005 our portfolio was leased to more than 165205 companies, many of which are nationally recognized firms. The following table sets forth information regarding the 15 largest tenants in our portfolio based on annualized rent as of December 31, 2004.2005.

Tenant		Property		Lease Expiration(1)		Total Leased Square Feet			Percentage of Net Rentable Square Feet(2)			Annualized Rent (thousands)			Percentage of Portfolio Annualized Rent
AT&T		11830 Webb Chapel Road		Nov. 2010		141,663			1.8				2,773		1.8
		7500 & 7520 Metro Center Drive		Mar. 2016		126,300			1.6				1,138		0.7
		1100 Space Park Drive		Jul. 2011		14,035			0.2				620		0.4
		600-780 S. Federal		Jan. 2006		5,137			0.1				171		0.1
		2323 Bryan Street		Sept. 2006		2,197			0.0				62		0.0
		200 Paul Avenue 1-4		Nov. 2009		10	(4)		0.0				18		0.0
		113 North Myers		Aug. 2011		1	(4)		0.0				3		0.0
						289,343			3.6				4,785		3.1
AboveNet, Inc.		150 South First Street		Nov. 2019		131,721			1.7				3,723		2.4
		600-780 S. Federal		Aug. 2010		19,112			0.2				655		0.4
		2323 Bryan Street		Apr. 2014		3,372			—				64		0.1
		200 Paul Avenue 1-4		Sept. 2010		10	(4)		—				33		—
						154,215			1.9				4,475		2.9
Leslie & Godwin(7)		6 Braham Street		Dec. 2009		63,233			0.8				3,816		2.5	(8)
Stone & Webster, Inc.(9)		100 Technology Center Drive		Mar. 2013		197,000			2.4				3,743		2.4
Maxtor Corporation(10)		47700 Kato Road & 1055 Page Avenue		Sep. 2011		183,050			2.3				3,472		2.2
XO Communications		200 Paul Avenue 1-4		Feb. 2015		64,907			0.8				2,098		1.3
		600 West Seventh Street		Aug. 2015		29,000			0.4				555		0.4
		600-780 S. Federal		Oct. 2006		322	(4)		—				100		0.1
		2323 Bryan Street		Oct. 2008		2,559			—				92		0.1
		350 East Cermak Road		Sept. 2015		1,747			—				61		—
		4055 Valley View Lane		Sept. 2009		343	(4)		—				7		—
						98,878			1.2				2,913		1.9
VSNL Networks, Inc.		1100 Space Park Drive		Nov. 2016		59,289			0.7				2,803		1.8
Thomas Jefferson University		833 Chestnut Street		Jul. 2008		63,500			0.8				938		0.6
		833 Chestnut Street		Apr. 2015		28,503			0.4				314		0.2
		833 Chestnut Street		Oct. 2010		18,017			0.2				297		0.2
		833 Chestnut Street		Dec. 2011		16,313			0.2				259		0.2
		833 Chestnut Street		Feb. 2011		12,787			0.2				189		0.1
		833 Chestnut Street		Aug. 2009		11,979			0.1				186		0.1
		833 Chestnut Street		Jun. 2012		7,068			0.1				112		0.1
		833 Chestnut Street		Nov. 2012		5,076			0.1				89		0.1
		833 Chestnut Street		Dec. 2008		6,312			0.1				87		0.1
		833 Chestnut Street		Nov. 2009		5,261			0.1				82		0.1
		833 Chestnut Street		Mar. 2008		2,379			—				33		—
		833 Chestnut Street		Feb. 2009		1,478			—				23		—
		833 Chestnut Street		Mar. 2012		986			—				17		—
						179,659			2.2				2,626		1.7
ASM Lithography		2010 East Centennial Circle		Feb. 2017		113,405			1.4				2,549		1.6
Total, Top 15 tenants						4,173,791			51.7	%		$	94,063		60.7	%