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                                                                    EXHIBIT 99.1

    FOR IMMEDIATE RELEASE:

               TYCO ANNOUNCES RESULTS OF ITS OFFER TO REPURCHASE
                  ZERO COUPON CONVERTIBLE DEBENTURES DUE 2021

    PEMBROKE, BERMUDA--FEBRUARY 13, 2003--Tyco International Ltd. (NYSE--TYC,
BSX--TYC, LSE--TYI) today announced the results of its offer to repurchase Zero
Coupon Convertible Debentures due February 12, 2021 issued by its wholly-owned
subsidiary, Tyco International Group S.A. Holders' option to surrender their
debentures for repurchase expired at 5:00 p.m., New York City time, on
February 12, 2003.

    Tyco has been advised by the depositary, U.S. Bank, N.A., that
$2,421,126,000 in aggregate principal amount at maturity of debentures were
validly surrendered for repurchase and not withdrawn and Tyco has repurchased
all of such debentures. The purchase price for the debentures was $764.15 in
cash per $1,000 in principal amount at maturity. The aggregate purchase price
for all of the debentures validly surrendered for repurchase and not withdrawn
was $1,850,103,433.

ABOUT TYCO INTERNATIONAL LTD.

    Tyco International Ltd. is a diversified manufacturing and service company.
Tyco operates in more than 100 countries and had fiscal 2002 revenues from
continuing operations of approximately $36 billion.

FORWARD-LOOKING STATEMENTS

    This release may contain certain "forward-looking statements" within the
meaning of the United States Private Securities Litigation Reform Act of 1995
(the "PSLRA"). These statements are based on management's current expectations
and are subject to risks, uncertainty and changes in circumstances, which may
cause actual results, performance or achievements to differ materially from
anticipated results, performance or achievements. All statements contained
herein that are not clearly historical in nature are forward-looking and the
words "anticipate," "believe," "expect," "estimate," "plan," and similar
expressions are generally intended to identify forward-looking statements. The
forward-looking statements in this release include statements addressing the
following subjects: future financial condition and operating results. Economic,
business, competitive and/or regulatory factors affecting Tyco's businesses are
examples of factors, among others, that could cause actual results to differ
materially from those described in the forward-looking statements. The PSLRA
safe harbor for forward-looking statements, however, does not apply to
forward-looking statements made in connection with Tyco's offer to repurchase
debentures surrendered by debenture holders.

    More detailed information about these and other factors is set forth in
Tyco's Annual Report on Form 10-K, as amended, for the fiscal year ended
September 30, 2002. Tyco is under no obligation to (and expressly disclaims any
such obligation to) update or alter its forward-looking statements whether as a
result of new information, future events or otherwise.

                                     # # #

Contact:  Gary Holmes (Media)
       212-424-1314
       Kathy Manning (Investors)
       603-334-3900