Income Per Share

3 Months Ended

Mar. 31, 2012

Income Per Share [Abstract]

Income Per Share

7. Income per Share

The following is a summary of basic and diluted income per share (in thousands, except share and per share amounts):

	Three Months Ended March 31,
	2012		2011
Net income available to common stockholders	$	39,211	$	30,980
Weighted average shares outstanding—basic		107,099,856		91,428,355
Potentially dilutive common shares:
Stock options		205,830		202,038
Class C Units (2007 Grant)		16,358		92,795
Unvested incentive units		262,812		153,066
Excess exchange value of the 2026 Debentures		—		723,961
Weighted average shares outstanding—diluted		107,584,856		92,600,215
Income per share:
Basic	$	0.37	$	0.34
Diluted	$	0.36	$	0.33

On or after July 15, 2026, the 4.125% exchangeable senior debentures due August 15, 2026 (the 2026 Debentures) would have been exchangeable at the then-applicable exchange rate for cash (up to the principal amount of the 2026 Debentures) and, with respect to any excess exchange value, into cash, shares of Digital Realty Trust, Inc. common stock or a combination of cash and shares of Digital Realty Trust, Inc. common stock. The 2026 Debentures also would have been exchangeable prior to July 15, 2026, but only upon the occurrence of certain specified events, including if the weighted average common stock price exceeded a specified strike price as of the end of a fiscal quarter. During the year ended December 31, 2011, the remaining 2026 Debentures were redeemed and exchanged. Using the treasury stock method, 723,961 shares of common stock contingently issuable upon settlement of the excess exchange value were included as potentially dilutive common shares in determining diluted earnings per share for the three months ended March 31, 2011.

We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive:

	Three Months Ended March 31,
	2012		2011
Weighted average of Operating Partnership common units not owned by us		4,332,966		4,874,253
Potentially dilutive 2029 Debentures		6,442,085		6,269,990
Potentially dilutive Series C Cumulative Convertible Preferred Stock		2,784,845		3,652,324
Potentially dilutive Series D Cumulative Convertible Preferred Stock		4,337,429		8,333,421
Potentially dilutive Series E Cumulative Redeemable Preferred Stock		4,025,863		—
		21,923,188		23,129,988