SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549 

FORM 11-K

(Mark One)
x 	ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934	
For the fiscal year ended December 31, 2011
OR
 
¨ 	TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934	
For the transition period from                  to                  
Commission File Number 1-8097

 
A.	Full title of the plan and the address of the plan, if different from that of the issuer named below:	
Ensco Multinational Savings Plan
 
B.	Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:	
Ensco plc
6 Chesterfield Gardens
London, England W1J 5BQ

 

ENSCO MULTINATIONAL SAVINGS PLAN
TABLE OF CONTENTS TO FINANCIAL STATEMENTS
AND SUPPLEMENTAL INFORMATION

Financial Statements:	  				
		
Report of Independent Registered Public Accounting Firm	  	 	1	  	
		
Statement of Net Assets Available for Benefits as of December 31, 2011	  	 	2	  	
		
Statement of Net Assets Available for Benefits as of December 31, 2010	  	 	3	  	
		
Statement of Changes in Net Assets Available for Benefits Year Ended December 31, 2011	  	 	4	  	
		
Statement of Changes in Net Assets Available for Benefits Year Ended December 31, 2010	  	 	5	  	
		
Notes to Financial Statements	  	 	6	  	
		
Supplemental Information:	  				
		
Schedule I - Investments as of December 31, 2011	  	 	12	  	
		
Signature	  	 	13	  	
		
Exhibits:	  				
		
Consent of Independent Registered Public Accounting Firm	  				

Report of Independent Registered Public Accounting Firm
To the Trustees of and Plan Administrator of the
Ensco Multinational Savings Plan
We have audited the accompanying statements of net assets available for benefits of the Ensco Multinational Savings Plan as of December 31, 2011 and 2010 and the related statements of changes in net assets available for benefits for the years then ended. These financial statements are the responsibility of the Plan’s management. Our responsibility is to express an opinion on these financial statements based on our audits.
We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. An audit includes consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Plan’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.
In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets available for benefits of the Ensco Multinational Savings Plan as of December 31, 2011 and 2010, and the changes in its net assets available for benefits for the year then ended in conformity with accounting principles generally accepted in the United States of America.
Our audits were conducted for the purpose of forming an opinion on the financial statements referred to above. The supplemental schedule of Schedule I – Investments as of December 31, 2011, is presented for the purpose of additional analysis and is not a required part of the financial statements. Such information has been subjected to the auditing procedures applied in the audit of the financial statements and, in our opinion, is fairly stated in all material respects in relation to the financial statements referred to above taken as a whole.
/s/ Whitley Penn LLP
Fort Worth, Texas
March 29, 2012
 
1

ENSCO MULTINATIONAL SAVINGS PLAN
STATEMENT OF NET ASSETS AVAILABLE FOR BENEFITS
AS OF DECEMBER 31, 2011

 	 	Total	 	 	Ensco plc
American
Depositary
Shares	 	 	Invesco
AIM US
Dollar
Liquidity
Portfolio	 	 	MFS
Meridian
Global
Equity
Fund	 	 	Pioneer
Funds-
North
American
Basic
Value	 	 	Templeton
Global
Bond
Fund	 	 	Skandia
Total
Return
USD
Bond
Fund	 	 	MFS
Meridian
Global
Total
Return
Fund	 	 	Legg
Mason
Global
Funds-
Royce
Smaller
Companies	 	 	Cash	 	
ASSETS:	 				 				 				 				 				 				 				 				 				 				
Investments at fair value:	 				 				 				 				 				 				 				 				 				 				
Other investments (cost $6,074,488)	 	$	6,297,753	  	 	$	—  	  	 	$	2,342,681	  	 	$	861,426	  	 	$	673,062	  	 	$	728,266	  	 	$	667,799	  	 	$	601,523	  	 	$	422,996	  	 	$	—  	  	
Ensco plc American depositary shares (cost $1,438,666)	 	 	1,475,165	  	 	 	1,475,165	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total investments	 	 	7,772,918	  	 	 	1,475,165	  	 	 	2,342,681	  	 	 	861,426	  	 	 	673,062	  	 	 	728,266	  	 	 	667,799	  	 	 	601,523	  	 	 	422,996	  	 	 	—  	  	
Cash	 	 	164,042	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	164,042	  	
Receivables:	 				 				 				 				 				 				 				 				 				 				
Employer contributions	 	 	1,550,118	  	 	 	212,573	  	 	 	607,072	  	 	 	166,087	  	 	 	116,741	  	 	 	127,638	  	 	 	107,412	  	 	 	104,711	  	 	 	98,199	  	 	 	9,685	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
NET ASSETS AVAILABLE FOR BENEFITS	 	$	9,487,078	  	 	$	1,687,738	  	 	$	2,949,753	  	 	$	1,027,513	  	 	$	789,803	  	 	$	855,904	  	 	$	775,211	  	 	$	706,234	  	 	$	521,195	  	 	$	173,727	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
The accompanying notes are an integral part of these financial statements.
 
2

ENSCO MULTINATIONAL SAVINGS PLAN
STATEMENT OF NET ASSETS AVAILABLE FOR BENEFITS
AS OF DECEMBER 31, 2010

 	 	Total	 	 	Ensco plc
American
Depositary
Shares	 	 	Invesco
AIM US
Dollar
Liquidity
Portfolio	 	 	MFS
Meridian
Global
Equity
Fund	 	 	Pioneer
Funds-
North
American
Basic
Value	 	 	Templeton
Global
Bond
Fund	 	 	Skandia
Total
Return
USD
Bond
Fund	 	 	MFS
Meridian
Global
Total
Return
Fund	 	 	Legg
Mason
Global
Funds-
Royce
Smaller
Companies	 	 	Cash	 	
ASSETS:	 				 				 				 				 				 				 				 				 				 				
Investments at fair value:	 				 				 				 				 				 				 				 				 				 				
Other investments (cost $3,916,858)	 	$	4,374,368	  	 	$	—  	  	 	$	1,504,777	  	 	$	662,645	  	 	$	519,488	  	 	$	519,634	  	 	$	458,692	  	 	$	412,248	  	 	$	296,884	  	 	$	—  	  	
Ensco plc American depositary shares (cost $1,178,384)	 	 	1,457,648	  	 	 	1,457,648	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total investments	 	 	5,832,016	  	 	 	1,457,648	  	 	 	1,504,777	  	 	 	662,645	  	 	 	519,488	  	 	 	519,634	  	 	 	458,692	  	 	 	412,248	  	 	 	296,884	  	 	 	—  	  	
Cash	 	 	133,818	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	133,818	  	
Receivables:	 				 				 				 				 				 				 				 				 				 				
Employer contributions	 	 	1,241,995	  	 	 	175,769	  	 	 	496,308	  	 	 	137,983	  	 	 	90,001	  	 	 	95,407	  	 	 	94,726	  	 	 	82,623	  	 	 	69,178	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
NET ASSETS AVAILABLE FOR BENEFITS	 	$	7,207,829	  	 	$	1,633,417	  	 	$	2,001,085	  	 	$	800,628	  	 	$	609,489	  	 	$	615,041	  	 	$	553,418	  	 	$	494,871	  	 	$	366,062	  	 	$	133,818	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
The accompanying notes are an integral part of these financial statements.
 
3

ENSCO MULTINATIONAL SAVINGS PLAN
STATEMENT OF CHANGES IN NET ASSETS AVAILABLE
FOR BENEFITS
YEAR ENDED DECEMBER 31, 2011

 	 	Total	 	 	Ensco plc
American
Depositary
Shares	 	 	Invesco
AIM US
Dollar
Liquidity
Portfolio	 	 	MFS
Meridian
Global
Equity
Fund	 	 	Pioneer
Funds-
North
American
Basic
Value	 	 	Templeton
Global
Bond
Fund	 	 	Skandia
Total
Return
USD
Bond
Fund	 	 	MFS
Meridian
Global
Total
Return
Fund	 	 	Legg
Mason
Global
Funds-
Royce
Smaller
Companies	 	 	Cash	 	
ADDITIONS TO NET ASSETS ATTRIBUTED TO:	 				 				 				 				 				 				 				 				 				 				
Investment income:	 				 				 				 				 				 				 				 				 				 				
Interest and dividends	 	$	43,526	  	 	$	42,706	  	 	$	627	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	193	  	
Realized gains	 	 	102,799	  	 	 	23,616	  	 	 	—  	  	 	 	31,458	  	 	 	13,476	  	 	 	6,424	  	 	 	10,131	  	 	 	5,244	  	 	 	12,450	  	 	 	—  	  	
Unrealized depreciation	 	 	(480,148	)	 	 	(241,380	)	 	 	—  	  	 	 	(86,905)	 	 	 	(67,981)	 	 	 	(32,825)	 	 	 	(1,378)	  	 	 	(3,700)	  	 	 	(45,979)	 	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total investment income (loss)	 	 	(333,823	)	 	 	(175,058	)	 	 	627	  	 	 	(55,447)	 	 	 	(54,505)	 	 	 	(26,401)	 	 	 	8,753	  	 	 	1,544	  	 	 	(33,529)	 	 	 	193	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Contributions:	 				 				 				 				 				 				 				 				 				 				
Participant	 	 	1,108,935	  	 	 	162,776	  	 	 	322,863	  	 	 	128,461	  	 	 	114,214	  	 	 	117,185	  	 	 	107,298	  	 	 	83,374	  	 	 	72,764	  	 	 	—  	  	
Employer	 	 	2,008,910	  	 	 	286,242	  	 	 	743,262	  	 	 	222,837	  	 	 	157,072	  	 	 	172,140	  	 	 	146,072	  	 	 	142,803	  	 	 	128,797	  	 	 	9,685	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total contributions	 	 	3,117,845	  	 	 	449,018	  	 	 	1,066,125	  	 	 	351,298	  	 	 	271,286	  	 	 	289,325	  	 	 	253,370	  	 	 	226,177	  	 	 	201,561	  	 	 	9,685	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
DEDUCTIONS FROM NET ASSETS ATTRIBUTED TO:	 				 				 				 				 				 				 				 				 				 				
Distributions to participants	 	 	(504,298	) 	 	 	(102,600	) 	 	 	(242,492	) 	 	 	(32,910	) 	 	 	(31,727	) 	 	 	(18,817	) 	 	 	(29,531	) 	 	 	(16,490	) 	 	 	(27,207)	  	 	 	(2,524)	  	
Administrative expenses	 	 	(475	) 	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	(475	) 	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total deductions	 	 	(504,773	) 	 	 	(102,600	) 	 	 	(242,492	) 	 	 	(32,910	) 	 	 	(31,727	) 	 	 	(18,817	) 	 	 	(29,531	) 	 	 	(16,490	) 	 	 	(27,207	) 	 	 	(2,999	) 	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
TRANSFERS, NET	 	 	—  	  	 	 	(117,039	) 	 	 	124,408	  	 	 	(36,056	) 	 	 	(4,740	) 	 	 	(3,244	)	 	 	(10,799	)	 	 	132	  	 	 	14,308	  	 	 	33,030	  	
NET INCREASE	 	 	2,279,249	  	 	 	54,321	  	 	 	948,668	  	 	 	226,885	  	 	 	180,314	  	 	 	240,863	  	 	 	221,793	  	 	 	211,363	  	 	 	155,133	  	 	 	39,909	  	
NET ASSETS AVAILABLE FOR BENEFITS:	 				 				 				 				 				 				 				 				 				 				
Beginning of year	 	 	7,207,829	  	 	 	1,633,417	  	 	 	2,001,085	  	 	 	800,628	  	 	 	609,489	  	 	 	615,041	  	 	 	553,418	  	 	 	494,871	  	 	 	366,062	  	 	 	133,818	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
End of year	 	$	9,487,078	  	 	$	1,687,738	  	 	$	2,949,753	  	 	$	1,027,513	  	 	$	789,803	  	 	$	855,904	  	 	$	775,211	  	 	$	706,234	  	 	$	521,195	  	 	$	173,727	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
The accompanying notes are an integral part of these financial statements.
 
4

ENSCO MULTINATIONAL SAVINGS PLAN
STATEMENT OF CHANGES IN NET ASSETS AVAILABLE
FOR BENEFITS
YEAR ENDED DECEMBER 31, 2010

 	 	Total	 	 	Ensco plc
American
Depositary
Shares	 	 	Invesco
AIM US
Dollar
Liquidity
Portfolio	 	 	MFS
Meridian
Global
Equity
Fund	 	 	Pioneer
Funds-
North
American
Basic
Value	 	 	Templeton
Global
Bond
Fund	 	 	Skandia
Total
Return
USD
Bond
Fund	 	 	MFS
Meridian
Global
Total
Return
Fund	 	 	Legg
Mason
Global
Funds-
Royce
Smaller
Companies	 	 	Cash	 	
ADDITIONS TO NET ASSETS ATTRIBUTED TO:	 				 				 				 				 				 				 				 				 				 				
Investment income:	 				 				 				 				 				 				 				 				 				 				
Interest and dividends	 	$	29,585	  	 	$	28,985	  	 	$	436	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	—  	  	 	$	164	  	
Realized gains	 	 	70,443	  	 	 	9,055	  	 	 	—  	  	 	 	13,581	  	 	 	14,041	  	 	 	7,687	  	 	 	8,662	  	 	 	8,907	  	 	 	8,510	  	 	 	—  	  	
Unrealized appreciation	 	 	516,269	  	 	 	328,253	  	 	 	—  	  	 	 	53,212	  	 	 	27,549	  	 	 	35,763	  	 	 	14,999	  	 	 	14,253	  	 	 	42,240	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total investment income	 	 	616,297	  	 	 	366,293	  	 	 	436	  	 	 	66,793	  	 	 	41,590	  	 	 	43,450	  	 	 	23,661	  	 	 	23,160	  	 	 	50,750	  	 	 	164	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Contributions:	 				 				 				 				 				 				 				 				 				 				
Participant	 	 	898,890	  	 	 	146,218	  	 	 	254,679	  	 	 	104,471	  	 	 	85,348	  	 	 	91,793	  	 	 	89,136	  	 	 	71,007	  	 	 	56,238	  	 	 	—  	  	
Employer	 	 	1,743,442	  	 	 	260,782	  	 	 	651,622	  	 	 	198,331	  	 	 	132,573	  	 	 	140,509	  	 	 	138,165	  	 	 	124,063	  	 	 	97,397	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total contributions	 	 	2,642,332	  	 	 	407,000	  	 	 	906,301	  	 	 	302,802	  	 	 	217,921	  	 	 	232,302	  	 	 	227,301	  	 	 	195,070	  	 	 	153,635	  	 	 	—  	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
DEDUCTIONS FROM NET ASSETS ATTRIBUTED TO:	 				 				 				 				 				 				 				 				 				 				
Distributions to participants	 	 	(427,524	) 	 	 	(105,351	) 	 	 	(196,359	) 	 	 	(33,394	) 	 	 	(38,916	) 	 	 	(22,080	) 	 	 	(3,700	) 	 	 	(17,894	) 	 	 	—  	  	 	 	(9,830	) 	
Administrative expenses	 	 	(200	) 	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	—  	  	 	 	(200	) 	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
Total deductions	 	 	(427,724	) 	 	 	(105,351	) 	 	 	(196,359	) 	 	 	(33,394	) 	 	 	(38,916	) 	 	 	(22,080	) 	 	 	(3,700	) 	 	 	(17,894	) 	 	 	—  	  	 	 	(10,030	) 	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
TRANSFERS, NET	 	 	—  	  	 	 	(45,211	) 	 	 	(37,483	) 	 	 	10,562	  	 	 	(4,025	) 	 	 	7,419	  	 	 	7,288	  	 	 	(15,030	) 	 	 	(8,926	) 	 	 	85,406	  	
NET INCREASE	 	 	2,830,905	  	 	 	622,731	  	 	 	672,895	  	 	 	346,763	  	 	 	216,570	  	 	 	261,091	  	 	 	254,550	  	 	 	185,306	  	 	 	195,459	  	 	 	75,540	  	
NET ASSETS AVAILABLE FOR BENEFITS:	 				 				 				 				 				 				 				 				 				 				
Beginning of year	 	 	4,376,924	  	 	 	1,010,686	  	 	 	1,328,190	  	 	 	453,865	  	 	 	392,919	  	 	 	353,950	  	 	 	298,868	  	 	 	309,565	  	 	 	170,603	  	 	 	58,278	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
End of year	 	$	7,207,829	  	 	$	1,633,417	  	 	$	2,001,085	  	 	$	800,628	  	 	$	609,489	  	 	$	615,041	  	 	$	553,418	  	 	$	494,871	  	 	$	366,062	  	 	$	133,818	  	
	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	 	
The accompanying notes are an integral part of these financial statements.
 
5

ENSCO MULTINATIONAL SAVINGS PLAN
NOTES TO FINANCIAL STATEMENTS
1. PLAN ORGANIZATION AND DESCRIPTION
The Ensco Multinational Savings Plan (the “Plan”) is a defined contribution plan available to international expatriate employees (“Eligible Employees”) of Ensco plc and subsidiaries (the “Company” or “Ensco”). The Plan was established on January 1, 2009 to provide a retirement benefit for Eligible Employees through Company profit sharing contributions and matching contributions based on Eligible Employee contributions, and to promote and encourage Eligible Employees to provide additional security and income for their retirement through a systematic savings program. Based upon current law and published interpretations, the Company does not believe that the Plan is subject to any of the provisions of the U.S. Employee Retirement Income Security Act of 1974, as amended. The following description of the Plan provides only general information. Participants in the Plan (“Plan Participants”) should refer to the Plan document for a more complete description of the Plan’s provisions.
Participation
Eligible Employees of the Company may participate in the Plan upon meeting certain service, citizenship or residency requirements if they are not employed in their own country of tax residency and are not contributing to, or receiving benefits from, any other employer-sponsored savings plan. Previously, Eligible Employees could elect to participate in the employee savings feature of the Plan after completing one month of service with the Company. Effective October 1, 2011, the Plan was amended by the Company to eliminate the one month employment eligibility requirement.
Eligible Employees automatically participate in the profit sharing feature of the Plan after completing at least 92 days of continuous full-time employment if they are employed at calendar year-end. The profit sharing contributions of the Company are at the discretion of the Board of Directors as disclosed below.
Contributions
Plan Participants may elect to make contributions to the Plan through salary and cash incentive award deferrals (“Savings Contributions”), which may or may not qualify for tax deferral based on each Plan Participant’s local tax requirements. Under the Plan, Savings Contributions are limited to 50% of the participant’s compensation and Plan Participants may elect to increase, decrease or suspend their Savings Contributions within certain limits, as defined in the Plan.
At the discretion of its Board of Directors, the Company may make contributions to the Plan (“Matching Contributions”). Matching Contributions may be made by the Company in the form of a stated dollar amount or in the form of a matching percentage of Savings Contributions. The Company made Matching Contributions to active participant Eligible Employee accounts as follows:

 	  	Matching Percentage	 	
 	  	2011	 	 	2010	 	
First 5% of eligible compensation	  	 	100	% 	 	 	100	% 	
Total Matching Contributions for the years ended December 31, 2011 and 2010 were $602,820 and $501,447, respectively.
 
6

At the discretion of its Board of Directors following close of a fiscal year, the Company may also make annual profit sharing contributions to the Plan for the benefit of all Plan Participants (“Profit Sharing Contributions”). Annual Profit Sharing Contributions are allocated to Plan Participants based on their proportionate compensation. The 2011 Profit Sharing contributions were awarded in cash in March 2012 totaling $1,406,090. The 2011 Profit Sharing Contributions were included in employer contributions in the statement of changes in net assets available for the year ended December 31, 2011. The 2010 Profit Sharing Contributions were awarded in cash in March 2011 totaling $1,241,995. The 2010 Profit Sharing Contributions were included in employer contributions in the statement of changes in net assets available for the year ended December 31, 2010.
Plan Administration
Assets in the Plan are held in trust by Citco Trustees (Cayman) Limited as original trustee on behalf of, and for the benefit of, Plan Participants, who was selected by the Board of Directors upon the recommendation of Company management. The trustee has the authority to manage or dispose of Plan assets as if it were the beneficial owner thereof. However, the trustee and the Company have delegated the management of day-to-day investment elections and administration of the Plan to Global Group Services Incorporated, the administrator, and UBS Financial, Inc., the custodian. Global Group Services Incorporated performs all recordkeeping services.
Vesting
A Plan Participant’s Matching Contribution account balance and Profit Sharing Contribution account balance become vested and nonforfeitable upon the completion of years of service with the Company, as follows:

Completed years of service	  	Vested percentage	 	
Less than one year	  	 	0	% 	
One year	  	 	33	% 	
Two years	  	 	67	% 	
Three or more years	  	 	100	% 	
A Plan Participant shall become fully vested in his or her Matching Contribution account balance and Profit Sharing Contribution account balance upon certain events, including death or disability, attaining the age of 65 or a period of service with the Company of at least three years, or a full termination of the Plan. A Plan Participant’s Savings Contribution account balance is fully vested at all times.
The unvested portion of Matching Contribution account balances and Profit Sharing Contribution account balances of terminated Plan Participants are forfeited to the Plan and may be used to pay certain administrative expenses of the Plan or to reduce the amount of future employer contributions. The Plan held forfeiture balances totaling $120,971 and $113,790 included in net assets available for benefits as of December 31, 2011 and 2010, respectively. The Plan did not use its forfeiture balance to reduce any portion of the Company’s Matching Contributions during the years ended December 31, 2011 and 2010.
Distributions
Distributions of a Plan Participant’s Savings Contribution account and the vested portion of a participant’s Matching Contribution account and Profit Sharing Contribution account generally are made within 60 days of an employee request due to termination of employment. As of December 31, 2011 and 2010, all Plan Participants who had elected to withdraw from the Plan had been paid.
 
7

Hardship Withdrawals
Should a Plan Participant experience a hardship, he or she may elect to withdraw all or part of his or her vested account from the Plan. All cases of hardship must be presented in writing to, and approved by, the Company. The Company may request additional supporting documentation from Plan Participants to substantiate any case of hardship. The Company may, at its discretion, approve all or part of the withdrawal request. Hardship withdrawals are recorded as distributions in the period in which they are paid. No hardship withdrawals were paid during the year ended December 31, 2011. During the year ended December 31, 2010, hardship withdrawals paid totaled $36,997.
Investments
The Plan allows participants to direct all contributions among a number of different investment funds held by UBS Financial, Inc., including Ensco American depositary shares, evidenced by Ensco American depositary receipts, which represent Class A Ordinary Shares of the Company (the “Ensco ADS Fund”). In addition, the Plan limits the portion of a participant’s aggregate account balance that may be invested in the Ensco ADS Fund to 25 percent. The daily value of each investment unit is determined by dividing the total fair market value of all assets in each fund by the total number of units in that fund. Investment income, including certain administrative fees and net appreciation (depreciation) of the fair value of investments, is allocated to each Plan Participant’s account based on the change in unit value for each investment fund in which the participant has an account balance.
2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Method of Accounting
The Plan’s financial statements are prepared on the accrual basis of accounting.
The Plan’s investments are stated at fair value using quoted market prices. Shares of mutual funds are valued at the net asset value of shares held by the Plan at year-end and there are no redemption restrictions associated with those investments. Purchases and sales of shares in mutual funds and the Ensco ADS Fund are recorded on a trade-date basis. Interest is recorded on the accrual basis and dividends are recorded on the ex-dividend date. See “Note 4 - Fair Value Measurements” for additional information on the fair value measurement of the Plan’s net assets.
The Plan presents in the statement of changes in net assets available for benefits the realized gains and/or losses and the unrealized appreciation (depreciation) on investments, which are calculated based on beginning of the year market values of investments to the date of sale and the purchase price, if purchased during the year, to the end of the year market value.
Estimates
The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires the Plan Sponsor to make estimates and assumptions that affect the reported amounts of assets and liabilities and related changes in net assets available for benefits, as well as disclosures of gain and loss contingencies at the date of the financial statements. Actual results could differ from those estimates.
Distributions
Distributions of benefits to Plan Participants are recorded when paid.
 
8

New Accounting Pronouncements
In May 2011, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update 2011-04, Amendments to Achieve Common Fair Value Measurements and Disclosure Requirements in U.S. GAAP and IFRS (“ASU 2011-04”). ASU 2011-04 amended ASC 820, Fair Value Measurements and Disclosures, to converge the fair value measurement guidance in U.S. GAAP and International Financial Reporting Standards (IFRSs). Some of the amendments clarify the application of existing fair value measurement requirements, while other amendments change a particular principle in ASC 820. In addition, ASU 2011-04 requires additional fair value disclosures. The amendments are to be applied prospectively and are effective for annual periods beginning after December 15, 2011. We will adopt Update 2011-04 upon its effective date of January 1, 2012. We do not expect the adoption of Update 2011-04 to have a material effect on the Plan’s financial statements.
3. PLAN INVESTMENTS
As of December 31, 2011 and 2010, the Plan’s investment options included the following:
Ensco ADS Fund: This fund is invested in the Company’s American depositary shares. The fund had 107 and 87 participants as of December 31, 2011 and 2010, respectively.
Invesco AIM US Dollar Liquidity Portfolio: This money market fund seeks to provide investors with a high level of current income, while preserving capital and maintaining liquidity by investing in a portfolio of high quality US dollar denominated short-term money market instruments. The fund had 146 and 109 participants as of December 31, 2011 and 2010, respectively.
MFS Meridian Global Equity Fund: This mutual fund seeks to provide investors capital appreciation by investing in a portfolio of equity securities of global issuers. The fund had 72 and 56 participants as of December 31, 2011 and 2010, respectively.
Pioneer Funds-North American Basic Value: This mutual fund seeks to provide investors capital appreciation over the medium to long-term by investing in a portfolio of equities and equity-linked instruments issued by companies that have their registered office in North America or that exercise the preponderant part of their economic activity in North America. The fund had 65 and 52 participants as of December 31, 2011 and 2010, respectively.
Templeton Global Bond Fund: This mutual fund seeks to provide investors a maximum total return, consisting of a combination of interest income and capital appreciation and currency gains by investing in a portfolio of fixed income securities worldwide. The fund had 70 and 50 participants as of December 31, 2011 and 2010, respectively.
Skandia Total Return USD Bond Fund: This mutual fund seeks to provide investors both current income and capital appreciation by investing in a portfolio of intermediate-term investment grade securities. The fund had 75 and 55 participants as of December 31, 2011 and 2010, respectively.
MFS Meridian Global Total Return Fund: This mutual fund seeks to provide investors total return by investing in a portfolio of large-cap equity securities and investment grade government bonds. The fund had 58 and 41 participants as of December 31, 2011 and 2010, respectively.
Legg Mason Global Funds-Royce Smaller Companies: This mutual fund seeks to provide investors long-term capital appreciation by investing in a portfolio of equity securities issued by mid-cap and small-cap companies with stock market capitalizations of less than US $5 billion. The fund had 58 and 41 participants as of December 31, 2011 and 2010, respectively.

During 2011 and 2010, the Plan’s investments, including gains and losses on investments bought and sold, as well as held during the year, appreciated (depreciated) in value as follows:

 	  	2011	 	 	2010	 	
Proceeds	  	$	673,605	  	 	$	576,673	  	
Aggregate cost	  	 	570,806	  	 	 	506,230	  	
	  	 	 	 	 	 	 	 	
Realized gains	  	 	102,799	  	 	 	70,443	  	
Unrealized (depreciation)/appreciation	  	 	(480,148	) 	 	 	516,269	  	
	  	 	 	 	 	 	 	 	
Net (depreciation)/appreciation in fair value of investments	  	$	(377,349	) 	 	$	586,712	  	
	  	 	 	 	 	 	 	 	
4. FAIR VALUE MEASUREMENTS
Certain provisions of FASB ASC 820-10 establish a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy assigns the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (“Level 1”) and the lowest priority to unobservable inputs (“Level 3”). Level 2 measurements are inputs that are observable for assets or liabilities, either directly or indirectly, other than quoted prices included within Level 1. The following fair value hierarchy table categorizes information regarding the Plan’s net assets measured at fair value on a recurring basis as of December 31, 2011 and 2010:

 	  	Quoted  Prices
in
Active  Markets
for
Identical Assets
(Level 1)	 	  	Significant
Other
Observable
Inputs
(Level 2)	 	  	Significant
Unobservable
Inputs
(Level 3)	 	  	Total	 	

	  			  			  			  			
	  			  			  			  			
As of December 31, 2011	  				  				  				  				
Other investments	  	$	6,297,753	 	  	$	—  	  	  	$	—  	  	  	$	6,297,753	 	
Ensco ADS Fund	  	 	1,475,165	 	  	 	—  	  	  	 	—  	  	  	 	1,475,165	 	
	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
Total investments	  	$	7,772,918	 	  	$	—  	  	  	$	—  	  	  	$	7,772,918	 	
	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
As of December 31, 2010	  				  				  				  				
Other investments	  	$	4,374,368	 	  	$	—  	  	  	$	—  	  	  	$	4,374,368	  	
Ensco ADS Fund	  	 	1,457,648	 	  	 	—  	  	  	 	—  	  	  	 	1,457,648	  	
	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
Total investments	  	$	5,832,016	 	  	$	—  	  	  	$	—  	  	  	$	5,832,016	  	
	  	 	 	 	  	 	 	 	  	 	 	 	  	 	 	 	
5. ADMINISTRATIVE FEES
The Plan has no employees. All administrative expenses of the Plan have been paid by the Company. Fees paid by the participants and the Plan for investment management and other related services amounted to approximately $475 and $200 for the years ended December 31, 2011 and 2010, respectively.
 
10

6. PLAN TERMINATION
Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan. In the event of Plan termination, participants will become 100% vested in their accounts.
7. TAX STATUS
The Plan is not qualified under Section 401(a) of the United States Internal Revenue Code of 1986, as amended.
In consideration that Plan Participants are not U.S. citizens, permanent residents or otherwise U.S. tax residents at any time they are participating, Plan Participants will not be directly subject to U.S. federal income tax on any dividends paid on stock of a U.S. corporation. However, the Cayman Islands trust that holds the Plan’s assets will be subject to U.S. federal income tax on such dividends at a rate of 30%, withheld at source. The trust will not be entitled to any lower tax treaty rates even if a Plan Participant would have been eligible for such lower treaty rates if he or she held the stock directly. Depending on a Plan Participant’s country of residence, he or she also may be entitled to a credit against his or her local income tax (if applicable) for the U.S. federal income tax withheld by the trust.
Accounting principles generally accepted in the United States of America require plan management to evaluate uncertain tax positions taken by the Plan. The financial statement effects of a tax position are recognized when the position is more-likely-than-not, based on the technical merits, to be sustained upon examination by the IRS. The plan administrator has analyzed the tax positions taken by the Plan and has concluded that, as of December 31, 2011, there are no uncertain positions taken or expected to be taken that would require recognition of a liability (or asset) or disclosure in the financial statements. The Plan is subject to routine audits by taxing jurisdictions; however, there are currently no audits for any tax periods in progress. The Company believes it is no longer subject to income tax examinations for years prior to 2008.
8. RELATED PARTY TRANSACTIONS
American depositary shares of the Company held by the Plan in the Ensco ADS Fund as an investment qualify as party-in-interest transactions. As of December 31, 2011 and 2010, the Plan’s investment in the Ensco ADS Fund was based on the closing price on such dates of $46.92 per share and $53.38 per share, respectively. Like any investment in publicly traded securities, the Company’s American depositary shares are subject to price changes. The high and low prices for the Company’s American depositary shares were $60.31 and $37.39 for 2011 and $53.93 and $33.33 for 2010. The Company’s American depositary shares totaled approximately 19% and 25% of the Plan’s total assets as of December 31, 2011 and 2010, respectively.
9. RISKS AND UNCERTAINTIES
The Plan invests in various investment options that are exposed to various risks such as interest rate, market and credit risks. Due to the level of risk associated with certain investments, it is at least reasonably possible that changes in the value of the investments will occur in the near term and that such changes could materially affect Plan Participants’ account balances and the amounts reported in the statement of net assets available for benefits.
 
11

Supplemental Information
Schedule I
ENSCO MULTINATIONAL SAVINGS PLAN
SCHEDULE I - INVESTMENTS
AS OF DECEMBER 31, 2011

Description	  	Number of
shares/units	 	  	Market
Value	 	  	Percentage
of Net
Assets	 	
Invesco AIM US Dollar Liquidity Portfolio	  	 	2,342,681	 	  	$	2,342,681	 	  	 	30.1	% 	
MFS Meridian Global Equity Fund	  	 	29,983	 	  	 	861,426	  	  	 	11.1	% 	
Pioneer Funds-North American Basic Value	  	 	11,980	 	  	 	673,062	  	  	 	8.7	% 	
Templeton Global Bond Fund	  	 	29,871	 	  	 	728,266	  	  	 	9.4	% 	
Skandia Total Return USD Bond Fund	  	 	39,740	 	  	 	667,799	  	  	 	8.6	% 	
MFS Meridian Global Total Return Fund	  	 	27,035	 	  	 	601,523	  	  	 	7.7	% 	
Legg Mason Global Funds-Royce Smaller Companies	  	 	4,195	 	  	 	422,996	  	  	 	5.4	% 	
				
Employer securities:	  				  				  				
*Ensco ADS Fund	  	 	31,440	 	  	 	1,475,165	 	  	 	19.0	% 	
	  	 	 	 	  	 	 	 	  	 	 	 	
Total Investments	  				  	$	7,772,918	 	  				

*	Party-in-interest	
 
12

SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the Administrator of the Plan has duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

	  		  	Ensco Multinational Savings Plan	
			
Date: March 29, 2012	  	 	  	/s/ DOUGLAS J. MANKO	
 	  	 	  	By: Douglas J. Manko	
 	  	 	  	       Controller of Ensco plc	
 
13

EXHIBIT INDEX

Exhibit No.	  	Description	
		
23.1	  	Consent of Independent Registered Public Accounting Firm	

Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in Registration Statement No. 333-156530 on Form S-8 of Ensco Multinational Savings Plan dated December 31, 2008, as amended by post-effective amendment No. 1 dated December 23, 2009, of our report dated March 29, 2012, with respect to the statements of net assets available for benefits of the Ensco Multinational Savings Plan as of December 31, 2011 and 2010, the related statements of changes in net assets available for benefits for the years then ended, and the related supplemental schedule of schedule I as of December 31, 2011, which report appears in the December 31, 2011 annual report on Form 11-K of the Ensco Multinational Savings Plan.
/s/ Whitley Penn LLP
Dallas, Texas
March 29, 2012