Edgar Filing: XL CAPITAL LTD

Filed Pursuant to Rule 424(b)(3)
Registration Statement No. 333-66976

PROSPECTUS SUPPLEMENT NO. 15
(To Prospectus Dated November 29, 2001)

$1,010,834,000

XL Capital Ltd
Zero-Coupon Convertible Debentures Due 2021
Exchangeable for Class A Ordinary Shares of
XL Capital Ltd

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This Prospectus Supplement supplements information contained in that
certain Prospectus dated November 29, 2001, as amended or supplemented, relating
to the potential sale from time to time by the Selling Securityholders of up to
$1,010,834,000 aggregate principal amount at maturity of Zero-Coupon Convertible
Debentures due 2021 (the "Debentures") of XL Capital Ltd, a Cayman Islands
exempted limited company, issued in a private transaction on May 23, 2001 and
Class A Ordinary Shares, par value US$0.01 each, of XL Capital Ltd (the
"Ordinary Shares"), issuable upon exchange of the Debentures. The Debentures are
being offered for the account of the holders thereof or by their transferees,
pledgees, donees or successors. This Prospectus Supplement is not complete
without, and may not be delivered or utilized except in connection with, the
Prospectus, including any amendments or supplements thereto. Capitalized terms
used herein but not defined have the meanings assigned to such terms in the
Prospectus.

The information contained in the table set forth in the Prospectus under
the caption "Selling Securityholders" shall be deleted and replaced in its
entirety with the information set forth below with respect to the Selling
Securityholders, the respective principal amount at maturity of Debentures owned
by the Selling Securityholders, and the respective principal amount of
Debentures offered by the Selling Securityholders hereby. Unless otherwise
indicated, none of the Selling Securityholders has, or within the past three
years has had, any position, office or other material relationship with XL
Capital Ltd or any of its affiliates. Because the Selling Securityholders may
offer all or some portion of their Debentures or the Ordinary Shares issued upon
exchange of their Debentures, pursuant to this Prospectus Supplement, no
estimate can be given as to the amount of the Debentures or the Ordinary Shares
issued upon exchange of the Debentures that will be held by the Selling
Securityholders upon termination of any sales. In addition, the Selling
Securityholders identified below may have sold, transferred or otherwise
disposed of all or a portion of their Debentures, or the Ordinary Shares issued
upon exchange of their Debentures, since the date on which they provided the
information regarding their Debentures, in transactions exempt from the
registration requirements of the Securities Act.

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Unless otherwise indicated, each Selling Securityholder is offering all
Debentures beneficially owned by them pursuant to this Prospectus Supplement. No
securityholder may offer their Debentures, or the Ordinary Shares issued upon
exchange of their Debentures, pursuant to this Prospectus Supplement until the
securityholder is named as a Selling Securityholder in this Prospectus
Supplement or in another supplement to the Prospectus.

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Aggregate Principal Percentage Number of Our Percentage of
Amount at Maturity of Ordinary Shares Our Ordinary
of Debentures That Debentures That May be Sold Shares Out-
Name May be Sold Outstanding (1) standing (2)
------------------------------------ --------------------- ------------- ----------------- -----------------

Tribeca Investments, L.L.C.......... 20,000,000 2.0 118,934 *

Continental Casualty Company........ 4,300,000 * 25,571 *

J.P. Morgan Securities Inc.......... 14,500,000 1.4 86,228 *

Lord Abbett Bond Debenture Fund,
Inc.............................. 12,500,000 1.2 74,334 *

CFFX, LLC........................... 11,000,000 1.1 65,414 *

MedAmerica Insurance c/o
Income Research & Management..... 2,900,000 * 17,245 *

MedAmerica New York Insurance c/o
Income Research & Management..... 1,200,000 * 7,136 *

Putnam Convertible Income-
Growth Trust..................... 9,110,000 * 54,174 *

Putnam Variable Trust-
Putnam VT Global Asset
Allocation Fund.................. 320,000 * 1,903 *

Putnam Convertible Opportunities and
Income Trust..................... 320,000 * 1,903 *

Putnam Asset Allocation
Funds-Balanced Portfolio......... 1,210,000 * 7,196 *

Putnam Asset Allocation
Funds-Conservative Portfolio..... 940,000 * 5,590 *

Lincoln National Global Asset
Allocation Fund, Inc............. 150,000 * 892 *

Museum of Fine Arts, Boston......... 30,000 * 178 *

Parker-Hannifin Corporation......... 250,000 * 1,487 *

Zola Partners, LP................... 600,000 * 3,568 *

Lyxor Master Fund................... 350,000 * 2,081 *

JMG Triton Offshore Fund, LTD....... 11,000,000 1.1 65,414 *

Highbridge International LLC........ 6,654,000 * 39,569 *

Medical Liability Mutual
Insurance Co..................... 4,500,000 * 26,760 *

Mag Mutual Insurance Co............. 125,000 * 743 *

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Landesbank Schleswig-Holstein
International S.A................ 30,000,000 3.0 178,401 *

Purchase Associates, L.P............ 559,000 * 3,324 *

Commonfund Event Driven Company c/o
IBT Fund Services (Cayman)....... 67,000 * 398 *

Levco Alternative Fund, Ltd......... 2,114,000 * 12,571 *

Continental Assurance Company
Separate Account (E)............. 700,000 * 4,163 *

Alta Partners Holdings, LDC......... 5,525,000 * 32,856 *

Aristeia Trading, LLC............... 3,675,000 * 21,854 *

Citi JL, Ltd........................ 88,000 * 523 *

Credit Suisse Asset Management...... 3,000,000 * 17,840 *

KBC Financial Products USA Inc...... 3,300,000 * 19,624 *

Lincoln National Convertible
Securities Fund.................. 3,250,000 * 19,327 *

AIG Soundshore Strategic Holding Fund
Ltd.............................. 10,895,000 1.1 64,789 *

AIG Soundshore Opportunity Holding
Fund Ltd........................ 13,105,000 1.3 77,932 *

Wilmington Trust Company as owner
trustee for the Forrestal Funding
Master Trust..................... 7,500,000 * 44,600 *

AXIS Capital Management Ltd......... 21,300,000 2.1 126,665 *

Goldman Sachs and Company........... 20,000,000 2.0 118,934 *

Morgan Stanley...................... 32,925,000 3.3 195,795 *

Credit Industriel D'Alsace Et De
Loraine.......................... 26,000,000 2.6 154,614 *

BNP Paribas Equity Strategies SNC LP 5,143,000 * 30,584 *

CooperNeff Convertible Strategies
Fund, L.P........................ 857,000 * 5,096 *

Societe Generale.................... 50,541,000 5.0 300,552 *

UBS AG London Branch................ 990,000 * 5,888 *

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Salomon Smith Barney Inc............ 8,930,000 * 53,104 *

Susquehanna Capital Group........... 7,500,000 * 44,600 *

AIG Soundshore Holdings Ltd......... 7,500,000 * 44,600 *

Tokai Asia Ltd...................... 20,000,000 2.0 118,934 *

First Union Securities Inc.......... 10,000,000 1.0 59,467 *

BTES - Convertible Arb.............. 1,000,000 * 5,947 *

BTPO - Growth vs Value.............. 1,000,000 * 5,947 *

Newport Investments Inc............. 1,700,000 * 10,109 *

KBC Financial Products (Cayman
Islands) Limited................. 12,000,000 1.2 71,360 *

Ellsworth Convertible Growth and Income
Fund, Inc........................ 1,500,000 * 8,920 *

Bancroft Convertible Fund, Inc...... 1,500,000 * 8,920 *

CDC IXIS Paris...................... 5,000,000 * 29,734 *

Beamtenkasse Des Kanton Zurich...... 3,000,000 * 17,840 *

Gaia Offshore Master Fund Ltd....... 3,450,000 * 20,516 *

Oppenheimer Convertible Securities
Fund ............................ 5,000,000 * 29,734 *

Salomon Brothers Asset Manage-
ment, Inc........................ 9,275,000 * 55,156 *

ADI Convex Valor.................... 5,500,000 * 32,707 *

UBS AG LON F/B/O PB................. 47,660,000 4.7 283,420 *

Deutsche Bank Securities Inc........ 4,346,000 * 25,844 *

Royal Bank of Canada Toronto........ 15,500,000 1.5 92,174 *

Banc of America Securities LLC...... 350,000 * 2,082 *

Bear Stearns International Limited
(BSIL)........................... 22,500,000 2.2 133,801 *

All other holders of Debentures or
future transferees, pledgees,
donees, assignees or successors
of any such holders(3)(4)........ 434,547,000 43.0 2,584,121 1.9

Total............................... 1,010,834,000 100.0 6,011,127 4.4

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* Less than one percent (1%).

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(1) Assumes conversion of all of the holder's Debentures at a conversion
rate of 5.9467 Ordinary Shares per $1,000 principal amount at maturity
of the Debentures. This conversion rate is subject to adjustment,
however, as described under "Description of the Debentures--Conversion
Rights." As a result, the number of our Ordinary Shares issuable upon
conversion of the Debentures may increase or decrease in the future.
Does not include our Ordinary Shares that may be issued by us upon
purchase of the Debentures by us at the option of the holder.

(2) Calculated based on Rule 13d-3(d)(i) of the Exchange Act, using
137,153,902 Ordinary Shares outstanding as of August 11, 2003. In
calculating this amount for each holder, we treated as outstanding the
number of our Ordinary Shares issuable upon conversion of all of that
holder's Debentures, but we did not assume conversion of any other
holder's Debentures. Does not include our Ordinary Shares that may be
issued by us upon purchase of the Debentures by us at the option of the
holder.

(3) Information about other selling securityholders will be set forth in
prospectus supplements, if required.

(4) Assumes that any other holders of Debentures, or any future pledgees,
donees, assignees, transferees or successors of or from any such other
holders of Debentures, do not beneficially own any of our Ordinary
Shares other than the Ordinary Shares issuable upon conversion of the
Debentures at the initial conversion rate.

All information in this Prospectus Supplement is as of September 19, 2003.

The date of this Prospectus Supplement is September 19, 2003.