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       [LETTERHEAD OF BEGHIN & FEIDER IN ASSOCIATION WITH ALLEN & OVERY]

                                                                     EXHIBIT 5.2

Tyco International Group S.A.
6, avenue Emile Reuter
Second Floor
L- 2420 Luxembourg

Luxembourg, September 14, 2000
MF/kl/2000704 / LU 12841

Ladies and Gentlemen:

    We have acted as legal advisers in the Grand-Duchy of Luxembourg
("Luxembourg") to Tyco International Group S.A. (the "Issuer"), a limited
liability company (SOCIETE ANONYME) now organized under the laws of Luxembourg
but formerly a company named "Velum Limited" organized under the laws of
Gibraltar which transferred its registered and principal office to Luxembourg on
March 30(th) 1998. We are giving this opinion in connection with the filing by
Tyco International Ltd., a Bermuda company ("Tyco"), and the Issuer, with the
United States Securities and Exchange Commission of a Registration Statement on
Form S-3, File Nos. 333-44100 and 333-44100-01 (as amended, the "Registration
Statement"), with respect to the Issuer's (i) unsecured debt securities (the
"Debt Securities"), (ii) the guarantees (the "Guarantees") of the Debt
Securities by Tyco and (iii) the Tyco common shares that may be issued upon
conversion or exchange of the Debt Securities (the "Common Shares"), to be
issued from time to time pursuant to Rule 415 under the United States Securities
Act of 1933, as amended (the "Securities Act"), for an aggregate initial
offering price not to exceed US$3,500,000,000. The Debt Securities are to be
issued in one or more series pursuant to Indentures among the Issuer, Tyco (as
Guarantor) and the trustees thereunder.

    We have examined copies of the following documents:

        (a) the Registration Statement;

        (b) the minutes of the extraordinary general meeting of shareholders of
    the Issuer held in notarial form before the notary Jean-Joseph Wagner on
    March 30(th), 1998 (the "Notarial Deed");

        (c) the restated articles of association of the Issuer in a version,
    dated March 30, 1998, published in the Official Gazette (Memorial) C-N(o)
    474 of June 29(th), 1998, an amendment to the articles of association of the
    Issuer by way of a notarial deed dated July 6(th), 1998 and published in the
    Official Gazette (Memorial) C-N(o) 733 of October 10(th), 1998, and an
    amendment to the articles of association of the Issuer by way of a notarial
    deed dated October 22(nd), 1998, published in the Official Gazette
    (Memorial) C-N(o) 44 of January 26(th), 1999, and an amendment to the
    articles of association of the Issuer by way of a notarial deed dated
    December 4(th), 1998, published in the Official Gazette (Memorial) C-N(o)
    144 of March 5(th), 1999, and an amendment to the articles of association of
    the Issuer by way of a notarial deed dated June 14(th), 1999, and published
    in the Official Gazette (Memorial) C-N(o) 692 of September 16(th), 1999;

        (d) an excerpt from the trade and company register at the district court
    in Luxembourg;

        (e) the board of directors' resolutions of the Issuer dated March 2,
    1999, resolving INTER ALIA the issue of the Debt Securities, the entry into
    any and all contractual documents in connection therewith (the "Agreements")
    and the filing of the Registration Statement; and

        (f) all other relevant corporate documents of the Issuer and such
    further documents and matters of law as we have considered necessary or
    appropriate for the rendering of this opinion.
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    For the purposes of this opinion, we have assumed with your consent, and we
have not verified independently, the following.

        (i) the genuineness of all the signatures and documents submitted to us
    as originals and the conformity to the originals thereof of the Registration
    Statement and other documents in respect of the Debt Securities submitted to
    us as copies or specimens;

        (ii) the due authorization, execution and delivery of all documents in
    respect of the Debt Securities by all the parties thereto (other than the
    Issuer), as well as the power, authority and legal right of all the parties
    thereto (other than the Issuer) to enter into, execute, deliver and perform
    their respective obligations thereunder, and compliance with all applicable
    laws and regulations, other than Luxembourg law;

        (iii) that all authorizations and consents of any country other than
    Luxembourg which may be required in connection with the execution, delivery
    and performance of the Agreements and other documents, including the
    Registration Statement, in respect of the issue of the Debt Securities have
    been or will be obtained;

        (iv) the validity and enforceability of the Agreements and other
    documents in respect of the Debt Securities under their governing laws
    (other than the laws of Luxembourg);

        (v) that the Debt Securities will not be the subject of a public
    offering in Luxembourg, unless the relevant requirements of Luxembourg law
    concerning public offerings of securities have been fulfilled; and

        (vi) that there are no provisions of the laws of any jurisdiction
    outside Luxembourg which would have any negative impact on the opinions we
    express in this legal opinion.

    Subject to the assumptions made above and the qualifications set forth
below, we are of the opinion as at the date hereof that:

        (1) The Issuer is a limited liability company validly organized and
    existing under the laws of Luxembourg and has all requisite corporate power
    and authority to issue the Debt Securities.

        (2) All necessary action required to be taken by the Issuer pursuant to
    the laws of Luxembourg has been taken by or on behalf of the Issuer and all
    the necessary authorizations and approvals of government authorities in
    Luxembourg have been duly obtained for the issue by the Issuer of the Debt
    Securities.

        (3) No filing with, or authorization, approval, consent, license, order,
    registration, qualification or decree of, any court or governmental
    authority or agency in Luxembourg is necessary or required to be made or
    obtained by Tyco or the Issuer in connection with the issue by the Issuer of
    the Debt Securities.

        (4) There are no taxes, duties, or other charges payable to or
    chargeable by the Government of Luxembourg, or any authority or agency
    thereof, in respect of the issue by the Issuer of the Debt Securities.

    The above opinions are subject to the following qualifications:

        a) Although this is rarely done in practice, if any or all Agreements or
    the Registration Statement were produced in Luxembourg proceedings or in
    front of a Luxembourg official authority, the court could order the
    registration thereof, in which case an ad valorem tax would be payable at
    the rate of 0.24 per cent., unless production was made in an enforceability
    claim under the provisions of the European Convention on Jurisdiction and
    Enforcement of Judgments in Civil and Commercial Matters signed at Brussels
    on 27(th) September, 1968, as amended.

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        b) This opinion is limited to matters of Luxembourg law only and we
    express no opinion other than with respect to Luxembourg law under the
    assumptions and reservations made hereunder.

        c) This opinion is as of this date and we undertake no obligation to
    update it or advise of changes hereafter occurring. We express no opinion as
    to any matters other than those expressly set forth herein, and no opinion
    is, or may be, implied or inferred herefrom.

    It should be noted that there are always irreconcilable differences between
languages making it impossible to guarantee a totally accurate translation or
interpretation. In particular, there are always some legal concepts which exist
in one jurisdiction and not in another, and in those cases it is bound to be
difficult to provide a completely satisfactory translation or interpretation
because the vocabulary is missing from the language.

    This opinion shall be construed in accordance with Luxembourg law and
Luxembourg legal concepts are expressed in English terms and not in their
original French terms. The concepts concerned may not be identical to the
concepts described by the same English terms as they exist under the laws of
other jurisdictions.

    This opinion may, therefore, only be relied upon under the express condition
that any issues of interpretation arising thereunder will be governed by
Luxembourg law and be brought before a Luxembourg court. Nothing in this opinion
should be taken as expressing an opinion in respect of any representations or
warranties, or other information, contained in the Prospectus included in the
Registration Statement or any other document examined in connection with the
opinion except as expressly confirmed herein.

    We hereby consent to the inclusion of the opinion as an exhibit to the
Registration Statement. We also consent to the reference to our firm under the
caption "Legal Matters" in the Prospectus included as part of the Registration
Statement.

                                        Yours faithfully,

                                        BEGHIN & FEIDER

                                        in association with

                                        ALLEN & OVERY

                                        /s/ MARC FEIDER
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                                        Marc Feider

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