Exhibit 99.1

XL Group
Insurance
Reinsurance

Press Release

Contact:	David Radulski	Carol Parker Trott
	Investor Relations	Media Relations
	(203) 964-3470	(441) 294-7290

XL GROUP PLC ANNOUNCES FIRST QUARTER 2012 RESULTS

• Operating net income¹ of $165.2 million, or $0.52 per share, for the quarter

• Net income of $176.6 million, or $0.56 per share, for the quarter

• Annualized operating return on ordinary shareholders’ equity² of 6.9%

• Natural catastrophe losses net of reinsurance and reinstatement premiums of $20.0 million recorded for the quarter

• Gross P&C premiums written for the year increased by 10.4% compared to the prior year quarter, primarily driven by new business lines, higher retention levels and certain pricing increases

• Fully diluted tangible book value per ordinary share³ of $29.58 at March 31, 2012, an increase of $1.27 from December 31, 2011 and an increase of $3.23 from March 31, 2011

¹ Defined as net income (loss) attributable to ordinary shareholders excluding (1) net realized gains and losses on investments, net of tax for XL, (2) net realized and unrealized gains and losses on derivatives, net of tax, for XL, (3) its share of items (1) and (2) for the Company’s insurance company affiliates for the periods presented, (4) goodwill impairment charges, net of tax, (5) the gains recognized on the repurchase of XLIT Ltd.’s preference ordinary shares and (6) foreign exchange gains or losses, net of tax. “Operating net income” and “return on ordinary shareholders’ equity” based on operating net income are “non-GAAP financial measures.” See the schedule entitled “Reconciliation” at the end of this release for a reconciliation of “operating net income” to net income (loss) attributable to ordinary shareholders and the calculation of “return on ordinary shareholders’ equity” based on operating net income to average ordinary shareholders’ equity.

² Ordinary shareholders’ equity is defined as total shareholders’ equity less non-controlling interest in equity of consolidated subsidiaries.

³ Book value per share, fully diluted book value per ordinary share and fully diluted tangible book value per ordinary share are non-GAAP financial measures. Fully diluted book value per share represents book value per ordinary share (total shareholders’ equity less non-controlling interest in equity of consolidated subsidiaries, divided by the number of outstanding ordinary shares at any period end) combined with the dilutive impact of potential future share issues at any period end. Fully diluted tangible book value per ordinary share is calculated in the same manner as fully diluted book value per ordinary share except that goodwill and intangible assets are removed from ordinary shareholders’ equity. The Company believes that fully diluted tangible book value per ordinary share is a financial measure important to investors and other interested parties who benefit from having a consistent basis for comparison with other companies within the industry. However, this measure may not be comparable to similarly titled measures used by companies either outside or inside of the insurance industry.

• Share buybacks during the quarter totaled 4.7 million shares for $100.0 million

Dublin, Ireland – May 8, 2012 – XL Group plc (“XL” or the “Company”) (NYSE: XL) today reported its first quarter 2012 results.

Commenting on the Company’s performance, Chief Executive Officer Mike McGavick said:

“We believe XL’s first quarter 2012 financial results are a solid step forward. In the quarter, we showed improvement in many of our most important metrics. We delivered both lower loss ratios and combined ratios in insurance and reinsurance. Our investment portfolio performed well, and we grew book value as we continued to buy back shares. We are pleased with our progress and we are resolved to continue this trend as demand for solutions to complex risks grows and pricing improves. The world-class talent we have assembled at XL is fully energized and focused.”

Highlights - Three months ended March 31
(U.S. Dollars in thousands except per share amounts)

	Three months ended March 31
	(Unaudited)
	2012		2011
Net income (loss) attributable to ordinary shareholders	$	176,628	$	(227,284	)
Per ordinary share-fully diluted	$	0.56	$	(0.73	)
Operating net income (loss) 1	$	165,231	$	(162,989	)
Per ordinary share-fully diluted	$	0.52	$	(0.52	)

Page 2 / 13

• Operating net income of $165.2 million compared to operating net loss of $163.0 million in the prior year quarter due primarily to significantly lower natural catastrophe losses.

• Net income in the quarter of $176.6 million compared to net loss of $227.3 million in the prior year quarter due primarily to operating losses and realized investment losses in the prior year quarter.

• Net investment income for the quarter was $265.2 million compared to $280.3 million in the prior year quarter and $270.9 million for the fourth quarter of 2011. The decline against the prior year quarter was primarily due to lower yields as a result of lower reinvestment rates and cash flows from the investment portfolio.

• Net income from investment fund and investment manager operating affiliates of $30.0 million in the quarter compared to income of $32.3 million in the prior year quarter.

• Net realized investment gains for the quarter of $20.8 million compared to losses of $66.4 million in the prior year quarter.

• Fully diluted book value per ordinary share increased by $1.29 from the prior quarter driven primarily by net income, unrealized gains on investments and the benefit of share buybacks.

• During the quarter, the Company purchased 4.7 million shares for $100.0 million at an average price of $21.14 per share, which was accretive to fully diluted book value per ordinary share by $0.14. $650.0 million of shares remains available for purchase under the Company’s previously announced $750 million share buyback program.

Page 3 / 13

P&C operations - Three months ended March 31

(U.S. Dollars in thousands)

	Three months ended March 31 (Unaudited)
	2012			2011
Gross premiums written	$	2,316,984		$	2,099,120
Net premiums written		1,963,228			1,714,282
Net premiums earned		1,357,898			1,271,696
Underwriting profit (loss)		63,240			(328,064	)
Loss ratio		62.9	%		95.1	%
Underwriting expense ratio		32.4	%		30.7	%
Combined ratio		95.3	%		125.8	%

• P&C gross premiums written (“GPW”) increased 10.4% from the prior year quarter. The Insurance segment saw an increase of 9.3% from the prior year quarter, as a result of new business initiatives in North America Property and Casualty lines, higher retention levels in Professional lines and improved pricing. The increase in GPW for the Reinsurance segment of 11.8% was primarily from the International Casualty line.

• P&C net premiums earned (“NPE”) of $1.4 billion was comprised of $934.1 million from the Insurance segment and $423.8 million from the Reinsurance segment. Compared to the prior year quarter, Insurance NPE increased by 6.6% and Reinsurance NPE increased by 7.1%.

• The P&C loss ratio was 32.2 percentage points lower than the prior year quarter. Included in the loss ratio was favorable prior year development of $80.3 million compared to $71.0 million in the prior year quarter. The loss ratio was also impacted by natural catastrophe losses of $20.0 million, net of reinsurance and reinstatement premiums. In the prior year quarter, natural catastrophe losses totaled $387.4 million, including reinstatement premiums. Excluding prior year development and natural catastrophe losses, the first quarter loss ratio was 2.5 percentage points lower than the prior year quarter

Page 4 / 13

	largely due to large marine and energy losses in the prior year quarter partially offset by a large marine loss in 2012.
•	Operating expenses were higher than in the first three quarters of 2011 but lower than the fourth quarter of 2011. Increased expenses versus the prior year quarter related largely to the build-out of the Company’s previously announced initiatives.
•	The P&C combined ratio excluding prior year development and the impact of natural catastrophe losses for the quarter was 99.8%, compared to 100.9% for the prior year quarter. The Insurance segment combined ratio on this basis was 104.8% for the quarter compared to 106.6% for the prior year quarter, while the Reinsurance segment combined ratio on this basis was 88.7% compared to 87.7% for the prior year quarter.

Further details of the results for the quarter may be found in the Company’s Financial Supplement, which is dated May 8, 2012 and is available from the Investor Relations section of the XL Group website.

A conference call to discuss the Company’s results will be held at 5 p.m. Eastern Time on Tuesday, May 8, 2012. The conference call can be accessed through a listen-only dial-in number or through a live webcast. To listen to the conference call, please dial (210) 795-0624 or (866) 617-1526: Passcode: “XL GLOBAL”. The webcast will be available at www.xlgroup.com and will be archived on XL’s website from approximately 9:00 p.m. Eastern Time on May 8, 2012, through midnight Eastern Time on June 8, 2012. A telephone replay of the conference call will also be available beginning at approximately 9:00 p.m. Eastern Time on May 8, 2012, until midnight Eastern Time on June 8, 2012, by dialing (203) 369-1011 or (866) 434-5271.

Page 5 / 13

About XL Group plc

XL Group plc, through its subsidiaries, is a global insurance and reinsurance company providing property, casualty and specialty products to industrial, commercial and professional firms, insurance companies and other enterprises throughout the world. XL is the company clients look to for answers to their most complex risks and to help move their world forward. Its principal offices are located at No.1 Hatch Street Upper, 4th Floor, Dublin 2, Ireland. To learn more, visit www.xlgroup.com.

This press release contains forward-looking statements. Statements that are not historical facts, including statements about XL’s beliefs, plans or expectations, are forward-looking statements. These statements are based on current plans, estimates and expectations, all of which involve risk and uncertainty. Statements that include the words “expect,” “intend,” “plan,” “believe,” “project,” “anticipate,” “will,” “may” or similar statements of a future or forward-looking nature identify forward-looking statements. Actual results may differ materially from those included in such forward-looking statements and therefore you should not place undue reliance on them. A non-exclusive list of the important factors that could cause actual results to differ materially from those in such forward-looking statements includes (a) changes in the size of XL’s claims relating to natural or man-made catastrophe losses due to the preliminary nature of some reports and estimates of loss and damage to date; (b) trends in rates for property and casualty insurance and reinsurance; (c) the timely and full recoverability of reinsurance placed by XL with third parties, or other amounts due to XL; (d) changes in ratings, rating agency policies or practices; (e) changes in the projected amount of ceded reinsurance recoverables; (f) XL’s ability to successfully implement its business strategy especially during a “soft” market cycle; (g) greater frequency or severity of claims and loss activity than XL’s underwriting, reserving or investment practices anticipate based on historical experience or industry data; (h) changes in general economic conditions, including the effects of inflation and changes in interest rates, credit spreads, foreign currency exchange rates and future volatility in the world’s credit, financial and capital markets that adversely affect the performance and valuation of XL’s investments or access to such markets; (i) developments,

Page 6 / 13

including uncertainties related to the ability of Euro-zone countries to service existing debt obligations and the strength of the Euro as a currency and to the financial condition of counterparties, reinsurers and other companies that are at risk of bankruptcy; (j) the impact of downgrades of U.S. securities by credit rating agencies or the European sovereign debt crisis, and the resulting effect on the value of securities (x) in our investment portfolio and (y) posted as collateral by and to us; (k) the potential for changes to methodologies, estimations and assumptions that underlie the valuation of XL’s financial instruments that could result in changes to investment valuations; (l) changes to XL’s assessment as to whether it is more likely than not that it will be required to sell, or has the intent to sell, available-for-sale debt securities before their anticipated recovery; (m) the ability of XL’s subsidiaries to pay dividends to XL Group plc and XLIT Ltd.; (n) the potential effect of regulatory developments in the jurisdictions in which XL operates, including those that could impact the financial markets or increase XL’s business costs and required capital levels; (o) changes in applicable tax laws, tax treaties or tax regulations or the interpretation or enforcement thereof; and (p) the other factors set forth in XL’s reports on Form 10-K, Form 10-Q and other documents on file with the Securities and Exchange Commission. XL undertakes no obligation to update publicly or revise any forward-looking statement, whether as a result of new information, future developments or otherwise.

XL intends to use its website as a means of disclosing material non-public information and for complying with its disclosure obligations under Regulation FD. Such disclosures will be included on the website in the Investor Relations section. Accordingly, investors should monitor such portions of XL’s website, in addition to following its press releases, SEC filings and public conference calls and webcasts.

###

Page 7 / 13

XL Group plc
SUMMARY CONSOLIDATED FINANCIAL DATA
(U.S. Dollars in thousands)

Income statement data:	Three months ended March 31
	(Unaudited)
	2012			2011
Revenues:
Gross premiums written:
- P&C operations	$	2,316,984		$	2,099,120
- Life operations		86,683			97,659
Net premiums written:
- P&C operations	$	1,963,228		$	1,714,282
- Life operations		78,496			89,672
Net premiums earned:
- P&C operations	$	1,357,898		$	1,271,696
- Life operations		78,520			89,687
Net investment income		265,242			280,263
Net realized (losses) gains on investments		20,803			(66,437	)
Net realized and unrealized (losses) gains on derivative instruments		702			3,567
Net income (loss) from investment fund affiliates		19,408			27,150
Fee income and other		9,859			8,932
Total revenues	$	1,752,432		$	1,614,858
Expenses:
Net losses and loss expenses incurred - P&C operations	$	854,065		$	1,208,865
Claims and policy benefits - Life operations		121,307			133,231
Acquisition costs		224,151			188,490
Operating expenses		282,411			260,992
Foreign exchange (gains) losses		12,718			9,514
Interest expense		39,298			54,147
Total expenses	$	1,533,950		$	1,855,239
Net income (loss) before income tax, net (income) loss from operating affiliates, and non-controlling interest	$	218,482		$	(240,381	)
Provision (benefit) for income tax		21,550			(32,797	)
Net (income) loss from operating affiliates		(16,253	)		(13,636	)
Net income (loss)	$	213,185		$	(193,948	)
Non-controlling interests		(36,557	)		(33,336	)
Net income (loss) attributable to XL Group plc and ordinary shareholders	$	176,628		$	(227,284	)

Page 8 /13

XL Group plc
SUMMARY CONSOLIDATED FINANCIAL DATA
(U.S. Dollars in thousands except per share amounts)

Selected balance sheet data:	As at March 31, 2012 (Unaudited)		As at December 31, 2011 (Note 1)
Total investments available for sale	$	28,135,057	$	27,017,285
Total fixed maturities, held to maturity		2,769,800		2,668,978
Cash and cash equivalents		2,506,318		3,825,125
Investments in affiliates		1,000,989		1,052,729
Unpaid losses and loss expenses recoverable		3,440,919		3,654,948
Goodwill and other intangible assets		408,878		407,321
Total assets (Note 2)		45,099,010		44,605,173
Unpaid losses and loss expenses		20,340,306		20,613,901
Deposit liabilities		1,590,188		1,608,108
Future policy benefit reserves		4,929,063		4,845,394
Unearned premiums		4,250,821		3,555,310
Notes payable and debt		1,674,653		2,275,327
Total shareholders’ equity (Note 2)		11,054,489		10,756,130
Ordinary shareholders’ equity (Note 2)		9,710,022		9,411,658
Ordinary shares outstanding (Note 3)		311,769,855		315,710,253
Basic book value per ordinary share (Note 2 and 4)	$	31.14	$	29.81
Fully diluted book value per ordinary share (Note 2 and 4)	$	30.88	$	29.59
Fully diluted tangible book value per ordinary share (Note 2 and 4)	$	29.58	$	28.31

Note 1: Certain items have been reclassified to conform to the current period presentation.

Note 2: On January 1, 2012, for all fiscal years and interim periods presented, the Company adopted a FASB accounting standards update to address disparities in practice regarding the interpretation of which costs relating to the acquisition of new and renewal insurance contracts qualify for deferral. This guidance was adopted on a retrospective basis. The impact of adoption of this guidance was a reduction in deferred acquisition costs of approximately $21 million, a reduction in deferred tax liabilities of approximately $7 million, and a corresponding reduction in opening retained earnings of approximately $14 million from the amounts presented in the Company’s December 31, 2011 balance sheet. The adoption of this guidance did not have an impact on the Company’s consolidated statements of income or comprehensive income.

Note 3: Ordinary shares outstanding include all ordinary shares legally issued and outstanding (as disclosed on the face of the balance sheet) as well as all director share units outstanding.

Note 4: Book value per share, fully diluted book value per ordinary share and fully diluted tangible book value per ordinary share are non-GAAP financial measures. Fully diluted book value per share represents book value per ordinary share (total shareholders’ equity less non-controlling interest in equity of consolidated subsidiaries, divided by the number of outstanding ordinary shares at any period end) combined with the dilutive impact of potential future share issues at any period end. Fully diluted tangible book value per ordinary share is calculated in the same manner as fully diluted book value per ordinary share except that goodwill and intangible assets are removed from ordinary shareholders’ equity.

Page 9 / 13

XL Group plc
RECONCILIATION

The following is a reconciliation of the Company’s net income (loss) attributable to ordinary shareholders to operating net income (loss) (Note 1) and also includes the calculation of annualized return on ordinary shareholders’ equity (based on operating net income (loss)) for the three months ended March 31, 2012 and 2011.

(U.S. Dollars in thousands except per share amounts)	Three months ended March 31 (Unaudited)
	2012			2011
				(Note 1)
Net income (loss) attributable to ordinary shareholders	$	176,628		$	(227,284	)
Net realized losses (gains) on investments, net of tax		(20,462	)		63,315
Net realized and unrealized losses (gains) on derivatives, net of tax		(697	)		(5,209	)
Net realized and unrealized (gains) losses on investments and derivatives related to the Company’s insurance company affiliates		(40	)		(874	)
Foreign exchange (gains) losses, net of tax		9,802			7,197
Gain on repurchase of non-controlling interest preference ordinary shares		—			(134	)
Operating net income (loss) (Note 2)	$	165,231		$	(162,989	)
Per ordinary share results:
Net income (loss) attributable to ordinary shareholders (Note 3)	$	0.56		$	(0.73	)
Operating net income (loss) (Note 2 and 3)	$	0.52		$	(0.52	)
Weighted average ordinary shares outstanding:
Basic		315,120,210			311,478,402
Diluted - Net income		317,639,325			311,478,402
Diluted - Operating net income		317,639,325			311,478,402
Return on ordinary shareholders’ equity:
Closing ordinary shareholders’ equity (Note 4 and 5)	$	9,710,022		$	9,253,918
Average ordinary shareholders’ equity (Note 4 and 5)	$	9,560,840		$	9,425,695
Operating net income (loss) (Note 2)	$	165,231		$	(162,989	)
Annualized operating net income (loss) (Note 2)	$	660,924			N/M
Annualized return on ordinary shareholders’ equity - operating net income (loss) (Notes 2, 4 and 5)		6.9	%		(6.9	%)

Note 1: Certain amounts have been reclassified to conform to the current period presentation.

Note 2: Defined as net income (loss) attributable to ordinary shareholders excluding (1) net realized gains and losses on investments, net of tax, for XL, (2) net realized and unrealized gains and losses on derivatives, net of tax, for XL, (3) its share of items (1) and (2) for the Company’s insurance company affiliates for the periods presented, (4) goodwill impairment charges, net of tax, (5) the gains recognized on the repurchase of XLIT Ltd.’s preference ordinary shares and (6) foreign exchange gains or losses, net of tax. “ Operating net income” and “ return on ordinary shareholders’ equity” based on operating net income are “ non-GAAP financial measures.”

Note 3: Diluted weighted average number of ordinary shares outstanding is used to calculate per share data except where it is anti-dilutive to earnings per share or where there is a net loss. When it is anti-dilutive or when a net loss occurs, basic weighted average ordinary shares outstanding is utilized in the calculation of net loss per share and net operating loss per share.

Note 4: Ordinary shareholders’ equity is defined as total shareholders’ equity less non-controlling interest in equity of consolidated subsidiaries.

Note 5: On January 1, 2012, for all fiscal years and interim periods presented, the Company adopted a FASB accounting standards update to address disparities in practice regarding the interpretation of which costs relating to the acquisition of new and renewal insurance contracts qualify for deferral. This guidance was adopted on a retrospective basis. The impact of adoption of this guidance was a reduction in deferred acquisition costs of approximately $21 million, a reduction in deferred tax liabilities of approximately $7 million, and a corresponding reduction in opening retained earnings of approximately $14 million from the amounts presented in the Company’s December 31, 2011 balance sheet. The adoption of this guidance did not have an impact on the Company’s consolidated statements of income or comprehensive income.

Page 10 / 13

Comment on Regulation G

XL presents its operations in the way it believes will be most meaningful and useful to investors, analysts, rating agencies and others who use XL’s financial information in evaluating XL’s performance. This press release contains the presentation of (i) operating net income (loss) (“Operating Net Income”), which is defined as net income (loss) attributable to ordinary shareholders excluding: (1) net realized gains and losses on investments net of tax, for XL, (2) net realized and unrealized gains and losses on derivatives, net of tax, for XL, (3) its share of items (1) and (2) for the Company’s insurance company affiliates for the periods presented, (4) goodwill impairment charges, net of tax, (5) the gains recognized on the repurchase of XLIT Ltd.’s preference ordinary shares and (6) foreign exchange gains or losses, net of tax, (ii) annualized return on ordinary shareholders’ equity (“ROE”) based on operating net income (loss) (“Operating ROE”) and (iii) book value per ordinary share (ordinary shareholders’ equity divided by the number of shares outstanding at the period end date), fully diluted book value per ordinary share (book value per share combined with the dilutive impact of potential future share issues at any period end), and fully diluted tangible book value per ordinary share (calculated in the same manner as fully diluted book value per ordinary share except that goodwill and intangible assets are removed from ordinary shareholders’ equity). These items are “non-GAAP financial measures” as defined in Regulation G. The reconciliation of such measures to the most directly comparable GAAP financial measures in accordance with Regulation G is included in this press release.

Although the investment of premiums to generate income (or loss) and realized capital gains (or losses) is an integral part of XL’s operations, the determination to realize capital gains (or losses) is independent of the underwriting process. In addition, under applicable GAAP accounting requirements, losses can be created as the result of other than temporary declines in value and from goodwill impairment charges without actual realization. In this regard, certain users of XL’s financial information, including certain rating agencies, evaluate earnings before tax and capital gains to understand the profitability of the recurring sources of income without the effects of these two

Page 11 / 13

variables. Furthermore, these users believe that, for many companies, the timing of the realization of capital gains and the recognition of goodwill impairment charges are largely a function of economic and interest rate conditions.

Net realized and unrealized (gains) losses on derivatives, net of tax include all derivatives entered into by XL other than certain credit derivatives. With respect to credit derivatives, because XL and its insurance company operating affiliates generally hold financial guaranty contracts written in credit default derivative form to maturity, the net effects of the changes in fair value of these credit derivatives are excluded (similar with other companies’ treatment of such contracts) as the changes in fair value each quarter are not indicative of underlying business performance.

The gains recognized on the repurchase of XLIT Ltd.’s preference ordinary shares are excluded as these transactions were capital in nature and outside the scope of the Company’s underlying business.

Foreign exchange gains and losses in the income statement are only one element of the overall impact of foreign exchange fluctuations on the Company’s financial position and are not representative of any economic gain or loss made by the Company. Accordingly, it is not a relevant indicator of financial performance and it is excluded.

In summary, XL evaluates the performance of and manages its business to produce an underwriting profit. In addition to presenting net income (loss), XL believes that showing operating net income (loss) enables investors and other users of XL’s financial information to analyze XL’s performance in a manner similar to how management of XL analyzes performance. In this regard, XL believes that providing only a GAAP presentation of net income (loss) makes it much more difficult for users of XL’s financial information to evaluate XL’s underlying business. Also, as stated above, XL believes that the equity analysts and certain rating agencies that follow XL (and the insurance industry as a whole) exclude these items from their analyses for the same reasons and they request that XL provide this non-GAAP financial information on a regular basis.

Page 12 / 13

Operating ROE is a widely used measure of any company’s profitability that is calculated by dividing annualized Operating Net Income for any period by the average of the opening and closing ordinary shareholders’ equity. The Company establishes target Operating ROEs for its total operations, segments and lines of business. If the Company’s Operating ROE targets are not met with respect to any line of business over time, the Company seeks to re-evaluate these lines.

Page 13 / 13