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                       SECURITIES AND EXCHANGE COMMISSION

                              Washington, DC 20549

                               -------------------

                                    FORM 8-K

                                 CURRENT REPORT

     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

                               -------------------

       Date of Report (Date of earliest event reported): January 17, 2003

                          AmerisourceBergen Corporation
             (Exact name of Registrant as specified in its charter)

Delaware                           1-16671                      23-3079390
(State or Other             Commission File Number           (I.R.S. Employer 
Jurisdiction of                                              Identification
Incorporation or                                             Number)
Organization)

                               -------------------


1300 Morris Drive, Suite 100
Chesterbrook, PA                                             19087
(Address of principal executive offices)                     (Zip Code)

Registrant's telephone number, including area code:  (610) 727-7000


                                       N/A
         (Former name or former address, if changed since last report.)

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Item 5. Other Events.

            On January 17, 2003, AmerisourceBergen Corporation (the "Company")
announced the closing of the acquisition of US Bioservices Corporation, a
national pharmaceutical service provider focused on the management of high-cost,
complex therapies and reimbursement support, for a base purchase price of 
approximately $160 million (including assumed debt). The transaction also
provides for contingency payments by the Company of up to a maximum of $28
million. The Company issued 2,399,091 shares of its common stock upon the
closing of the transaction. The Company has registered such shares under the
Securities Act of 1933 for sale by the recipients thereof.

            A copy of the press release is filed as Exhibit 99.1 to this report
and incorporated herein by reference.



Item 7. Financial Statements and Exhibits.

            (c)   Exhibits.
                  99.1     Press Release dated January 17, 2003

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                                   SIGNATURES

            Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                                    AMERISOURCEBERGEN CORPORATION

Date: January 17, 2003             By:    /s/  Michael D. DiCandilo
                                    -----------------------------------
                                    Name:  Michael D. DiCandilo
                                    Title:  Senior Vice President
                                            and Chief Financial Officer




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[AMERISOURCEBERGEN LOGO]                           AmerisourceBergen Corporation
                                                   P.O. Box 959
                                                   Valley Forge, PA  19482  



CONTACT:    MICHAEL N. KILPATRIC
            610-727-7118
            MKILPATRIC@AMERISOURCE.COM


                           AMERISOURCEBERGEN COMPLETES
                    ACQUISITION OF US BIOSERVICES CORPORATION

    Largest Pharmaceutical Distributor Adds Specialty Pharmaceutical Services
                                    Business

VALLEY FORGE, Pa. January 17, 2003--AmerisourceBergen Corporation (NYSE:ABC),
the largest pharmaceutical services company in the U.S. dedicated solely to the
pharmaceutical supply channel, today completed the acquisition of US Bioservices
Corporation, a privately held company (approximately 58 percent of which is
owned by Whitney and Company), for a base purchase price of approximately $160
million, including assumed debt. The transaction also provides for contingent
payments of up to $28 million based on US Bioservices achieving defined earnings
targets through the end of the first quarter of calendar year 2004.

      AmerisourceBergen expects the acquisition to be slightly accretive to the
Company's fiscal 2003 earnings per share.

      AmerisourceBergen issued approximately 2.4 million shares of its common
stock and paid approximately $12 million in cash to the stockholders
 of US
Bioservices upon the closing of the transaction today. The shares of
AmerisourceBergen common stock issued upon the closing of the transaction have
been registered under the Securities Act of 1933 for sale by the recipients of
the shares and, therefore, are eligible for sale immediately without
restriction.

      US Bioservices is a national pharmaceutical services provider focused on
the management of high-cost, complex therapies and reimbursement support. US
Bioservices had revenues of about $125 million in the 2002 calendar year.

ABOUT AMERISOURCEBERGEN

AmerisourceBergen (NYSE:ABC) is the largest pharmaceutical services company in
the United States dedicated solely to the pharmaceutical supply chain. It is the
leading distributor of pharmaceutical products and services to the hospital
systems/acute care market, alternate care and mail order facilities,

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                                                                    NEWS RELEASE


independent community pharmacies, and regional chain pharmacies. The Company is
also a leader in the institutional pharmacy marketplace. With more than $40
billion in annualized operating revenue, AmerisourceBergen is headquartered in
Valley Forge, PA, and employs more than 13,000 people serving over 25,000
customers. For more information go to www.amerisourcebergen.com.

FORWARD-LOOKING STATEMENTS 

THIS NEWS RELEASE MAY CONTAIN CERTAIN "FORWARD-LOOKING STATEMENTS" WITHIN THE
MEANING OF SECTION 27A OF THE SECURITIES ACT OF 1933 AND SECTION 21E OF THE
SECURITIES EXCHANGE ACT OF 1934. THESE STATEMENTS ARE BASED ON MANAGEMENT'S
CURRENT EXPECTATIONS AND ARE SUBJECT TO UNCERTAINTY AND CHANGES IN
CIRCUMSTANCES. ACTUAL RESULTS MAY VARY MATERIALLY FROM THE EXPECTATIONS
CONTAINED IN THE FORWARD-LOOKING STATEMENTS. FORWARD-LOOKING STATEMENTS MAY
INCLUDE STATEMENTS ADDRESSING FUTURE FINANCIAL AND OPERATING RESULTS OF
AMERISOURCEBERGEN AND THE BENEFITS AND ASPECTS OF THE 2001 MERGER BETWEEN
AMERISOURCE HEALTH CORPORATION AND BERGEN BRUNSWIG CORPORATION.

THE FOLLOWING FACTORS, AMONG OTHERS, COULD CAUSE ACTUAL RESULTS TO DIFFER
MATERIALLY FROM THOSE DESCRIBED IN THE FORWARD-LOOKING STATEMENTS: THE RISK THAT
THE BUSINESSES OF AMERISOURCE AND BERGEN BRUNSWIG WILL NOT BE INTEGRATED
SUCCESSFULLY; FAILURE TO OBTAIN AND RETAIN EXPECTED SYNERGIES; AND OTHER
ECONOMIC, BUSINESS, COMPETITIVE AND/OR REGULATORY FACTORS AFFECTING THE BUSINESS
OF AMERISOURCEBERGEN GENERALLY.

MORE DETAILED INFORMATION ABOUT THESE FACTORS IS SET FORTH IN
AMERISOURCEBERGEN'S FILINGS WITH THE SECURITIES AND EXCHANGE COMMISSION,
INCLUDING ITS ANNUAL REPORT ON FORM 10-K FOR FISCAL 2002.

AMERISOURCEBERGEN IS UNDER NO OBLIGATION TO (AND EXPRESSLY DISCLAIMS ANY SUCH
OBLIGATION TO) UPDATE OR ALTER ANY FORWARD-LOOKING STATEMENTS WHETHER AS A
RESULT OF NEW INFORMATION, FUTURE EVENTS OR OTHERWISE.