Diamond Offshore Drilling (DODRW) 8-K Diamond Offshore Drilling, Inc. Announces First Quarter 2010 Results

Exhibit 99.1

FOR IMMEDIATE RELEASE	CONTACT: Les Van Dyke
	Director, Investor Relations
	(281) 492-5370

DIAMOND OFFSHORE DRILLING, INC. ANNOUNCES
FIRST QUARTER 2010 RESULTS

Houston, Texas, April 22, 2010 — Diamond Offshore Drilling, Inc. (NYSE:DO) today reported net income for the first quarter of 2010 of $290.9 million, or $2.09 per share on a diluted basis, compared with net income of $348.6 million, or $2.51 per share on a diluted basis, in the same period a year earlier. Revenues in the first quarter of 2010 were $859.7 million, compared with revenues of $885.7 million for the first quarter of 2009.

In addition, in a related statement today, the Company announced its regular quarterly dividend of $0.125 per share of common stock, and a special dividend of $1.375 per share of common stock. The special dividend represents a reduction of $0.50 per share from the previous special dividend, reflecting current and anticipated industry conditions, including a decline in renewal contract dayrates from peak levels. The Company also considers it prudent at this time to retain cash for potential rig acquisition opportunities and other corporate purposes.

Larry Dickerson, President and CEO, stated, “Since Diamond Offshore began paying a special dividend in January 2006, we have paid out to shareholders total dividends of $23.88 per share, or approximately $3.3 billion. These dividend payments are an important part of our efforts to enhance shareholder value, and our revised special quarterly dividend continues these efforts while maintaining the Company’s financial strength and strategic flexibility.”

Mr. Dickerson continued, “We believe that the new level of special quarterly dividend can be maintained at least through 2010, although any decision by our Board to declare a special dividend, as well as the amount of any special dividend that may be declared, will be based on the Company’s financial position, earnings, earnings outlook, capital spending plans, and other relevant factors at that time.

Diamond Offshore provides contract drilling services to the energy industry and is a leader in deepwater drilling. Additional information on Diamond Offshore and access to the Company’s SEC filings is available on the Internet atwww.diamondoffshore.com.

As previously announced, Diamond Offshore will provide a simulcast and rebroadcast of its first quarter 2010 earnings release conference call. The live broadcast of our quarterly conference call will be available online atwww.diamondoffshore.com on April 22, 2010 beginning at 9:00 a.m. Central Daylight Time. The online replay will follow immediately and continue for the remainder of the calendar quarter after the original call. Please go to

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the web site at least 15 minutes before the broadcast to register, download and install any necessary audio software.

Statements contained in this press release which are not historical facts are “forward-looking statements” within the meaning of the federal securities laws. Forward-looking statements are inherently uncertain and subject to a variety of risks that could cause actual results to differ materially from those expected by management of the Company. A discussion of the important risk factors and other considerations that could materially impact these matters as well as the Company’s overall business and financial performance can be found in the Company’s reports filed with the Securities and Exchange Commission and readers of this release are urged to review those reports carefully when considering these forward-looking statements. Copies of these reports are available through the Company’s websitewww.diamondoffshore.com. Given these risk factors, investors and analysts should not place undue reliance on forward-looking statements. Any such forward-looking statements speak only as of the date of this press release. The Company expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statement to reflect any change in the Company’s expectations with regard thereto or any change in events, conditions or circumstances on which any forward-looking statement is based.

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DIAMOND OFFSHORE DRILLING, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS
(Unaudited)
(In thousands, except per share data)

	Three Months Ended
	March 31,
	2010			2009
Revenues:
Contract drilling	$	844,438		$	855,708
Revenues related to reimbursable expenses		15,243			30,012
Total revenues		859,681			885,720
Operating expenses:
Contract drilling		305,127			297,747
Reimbursable expenses		14,705			29,715
Depreciation		97,402			85,062
General and administrative		16,654			16,315
Gain on disposition of assets		(884	)		(55	)
Total operating expenses		433,004			428,784
Operating income		426,677			456,936
Other income (expense):
Interest income		1,282			576
Interest expense		(22,321	)		(1,117	)
Foreign currency transaction gain (loss)		461			(4,125	)
Other, net		(87	)		1,067
Income before income tax expense		406,012			453,337
Income tax expense		(115,159	)		(104,756	)
Net income	$	290,853		$	348,581
Earnings per share:
Basic	$	2.09		$	2.51
Diluted	$	2.09		$	2.51
Weighted average shares outstanding:
Shares of common stock		139,026			139,001
Dilutive potential shares of common stock		103			63
Total weighted average shares outstanding		139,129			139,064

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DIAMOND OFFSHORE DRILLING, INC. AND SUBSIDIARIES
RESULTS OF OPERATIONS
(Unaudited)
(In thousands)

	Three Months Ended
	March 31,
	2010			2009
REVENUES
High Specification Floaters	$	383,788		$	312,134
Intermediate Semisubmersibles		380,701			417,000
Jack-ups		79,949			126,574
Total Contract Drilling Revenue	$	844,438		$	855,708
Revenues Related to Reimbursable Expenses	$	15,243		$	30,012
CONTRACT DRILLING EXPENSE
High Specification Floaters	$	109,155		$	93,628
Intermediate Semisubmersibles		138,599			130,715
Jack-ups		52,528			68,918
Other		4,845			4,486
Total Contract Drilling Expense	$	305,127		$	297,747
Reimbursable Expenses	$	14,705		$	29,715
OPERATING INCOME
High Specification Floaters	$	274,633		$	218,506
Intermediate Semisubmersibles		242,102			286,285
Jack-ups		27,421			57,656
Other		(4,845	)		(4,486	)
Reimbursable expenses, net		538			297
Depreciation		(97,402	)		(85,062	)
General and administrative expense		(16,654	)		(16,315	)
Gain on disposition of assets		884			55
Total Operating Income	$	426,677		$	456,936

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DIAMOND OFFSHORE DRILLING, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATED BALANCE SHEETS
(In thousands)

	March 31,		December 31,
	2010		2009
	(unaudited)
ASSETS
Current assets:
Cash and cash equivalents	$	306,054	$	376,417
Marketable securities		650,756		400,853
Accounts receivable, net of provision for bad debts		797,932		791,023
Prepaid expenses and other		146,913		155,077
Total current assets		1,901,655		1,723,370
Drilling and other property and equipment, net of accumulated depreciation		4,414,387		4,432,052
Other assets		408,761		108,839
Total assets	$	6,724,803	$	6,264,261
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Payable for marketable securities purchased	$	99,989	$	—
Other current liabilities		724,737		413,475
Total current liabilities		824,726		413,475
Long-term debt		1,495,428		1,495,375
Deferred tax liability		540,669		546,024
Other liabilities		220,837		178,745
Stockholders’ equity		3,643,143		3,630,642
Total liabilities and stockholders’ equity	$	6,724,803	$	6,264,261

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DIAMOND OFFSHORE DRILLING, INC. AND SUBSIDIARIES
AVERAGE DAYRATES AND UTILIZATION

	First Quarter					Fourth Quarter					First Quarter
	2010					2009					2009
	Dayrate		Utilization			Dayrate		Utilization			Dayrate		Utilization
						(Dayrate in thousands)							��
High Specification Floaters	$	400		79	%	$	388		81	%	$	360		80	%
Intermediate Semis	$	276		78	%	$	280		78	%	$	283		85	%
Jack-ups	$	100		63	%	$	112		63	%	$	131		73	%

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