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                                                                     EXHIBIT 8.2

                        [Shearman & Sterling Letterhead]




                                July 26, 2001



Bergen Brunswig Corporation
4000 Metropolitan Drive
Orange, CA  92868




Ladies and Gentlemen:

               We are acting as counsel to Bergen Brunswig Corporation, a New
Jersey corporation ("Bergen") in connection with the proposed merger of B-Sub
Acquisition Corp., a New Jersey corporation ("Bergen Merger Sub") with and into
Bergen (the "Bergen Merger") and the proposed merger of A-Sub Acquisition Corp.,
a Delaware corporation ("AmeriSource Merger Sub") with and into AmeriSource
Health Corporation, a Delaware corporation, ("AmeriSource") (the "AmeriSource
Merger" and, together with the Bergen Merger, the "Mergers") pursuant to an
Agreement and Plan of Merger dated as of March 16, 2001 among AABB Corporation
(now known as AmeriSourceBergen Corporation), a Delaware corporation,
AmeriSource, Bergen, AmeriSource Merger Sub and Bergen Merger Sub (the "Merger
Agreement"). AmeriSourceBergen Corporation, a Delaware corporation
("AmeriSourceBergen"), is filing with the Securities and Exchange Commission
(the "Commission") under the Securities Act of 1933, amended (the "Act"), a
registration statement on Form S-4 (the "Registration Statement") dated as of
the date hereof, with respect to the common stock of AmeriSourceBergen to be
issued to holders of shares of Common Stock of AmeriSource and holders of shares
of Common Stock of Bergen in connection with the Mergers and the related Joint
Proxy Statement/Prospectus of AmeriSource and Bergen (the "Joint Proxy
Statement/Prospectus"). At your request in connection with the filing of the
Registration Statement, we are rendering our opinion concerning certain federal
income tax consequences of the Bergen Merger.

               For purposes of the opinion set forth below, we have, with the
consent of AmeriSource and the consent of Bergen, relied upon the accuracy and
completeness of the statements and representations (which statements and
representations we have neither investigated nor verified) and covenants
contained in the Merger Agreement and those contained in the certificates of
AmeriSource and Bergen each dated July 26, 2001 (copies of
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Bergen Brunswig Corporation               - 2 -                   July 26, 2001



which are attached hereto and which are incorporated herein by reference), and
have assumed that such statements and representations will be complete and
accurate as of the Effective Time and those covenants will be complied with in
all material respects. We have also relied upon the accuracy of the Registration
Statement and the Joint Proxy Statement/Prospectus. Any capitalized term used
and not defined herein has the meaning given to it in the Proxy
Statement/Prospectus or the Merger Agreement, as the case may be.

               We have also assumed that the transactions contemplated by the
Merger Agreement will be consummated in accordance therewith and as described in
the Joint Proxy Statement/Prospectus and that the Bergen Merger will qualify as
a statutory merger under applicable state laws.

               Based upon and subject to the foregoing, and based upon the
Internal Revenue Code of 1986, as amended (the "Code"), the Treasury Regulations
promulgated thereunder, judicial decisions, revenue rulings and revenue
procedures of the Internal Revenue Service, and other administrative
pronouncements, all as in effect on the date hereof, it is our opinion that:

               1. Neither Bergen nor holders of shares of Bergen Common Stock
will recognize any gain or loss for federal income tax purposes in connection
with the Bergen Merger, except to the extent that cash may be received in lieu
of Fractional Shares and to the extent of any payments made in respect of
conveyance taxes pursuant to Section 6.1(i) of the Merger Agreement;

               2. Subject to the limitations set forth therein, the discussion
contained in the Joint Proxy Statement/Prospectus under the caption "The Merger
- - Material United States federal income tax consequences of the Merger" is an
accurate summary of the material U.S. federal income tax consequences of the
Bergen Merger to holders of shares of Bergen Common Stock under currently
applicable law.

               No opinion is expressed as to any matter not specifically
addressed above, including the accuracy of the representations or reasonableness
of the assumptions relied upon by us in rendering the opinion set forth above.
The opinion is furnished to you solely for your exclusive use, and it may not be
distributed, published, or relied upon by any other person without our prior
written consent. Our opinion is based on current United States federal income
tax law and administrative practice, and we do not undertake to advise you as to
any future changes in United States federal income tax law or administrative
practice that may affect our opinion unless we are specifically retained to do
so. Further, legal opinions are not binding upon the Internal Revenue Service
and there can be no assurance that contrary positions may not be asserted by the
Internal Revenue Service.

               We hereby consent to the filing of this opinion with the
Commission as an exhibit to the Registration Statement and to the reference to
us under the caption "The Merger - -Material United States federal income tax
consequences of the Merger" and elsewhere in the

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Bergen Brunswig Corporation               - 3 -                    July 26, 2001


Proxy Statement/Prospectus. In giving such consent, we do not hereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Act and the rules and regulations of the Commission promulgated thereunder.




                                                         Very truly yours,


                                                         /s/ Shearman & Sterling




MKW/AFS/JBZ