SecProbe.io

April 18 , 2012

Via e -mail
Tim G. Guttman
Executive  Vice President , Controller  and
   Acting Chief Financial  Officer
AmerisourceBergen Corporation
1300 Morris Drive
Chesterbrook, PA 19087 -5594

Re: AmerisourceBergen Corporation
 Form 10-K for the Year Ended September 30 , 2011
Filed November 22 , 2011
Response dated  April 2, 2012
File No. 001 -16671

Dear Mr. Guttman :

We have reviewed your filing and response and have the following comments.  In some
of our comments, we may ask you to provide us with information so we may better understand
your disclosure.

Please respond to this letter within ten business days by amending your filing, by
providing the requested information, or by ad vising us when you will provide the requested
response.   If you do not believe our comments apply to your facts and circumstances or do not
believe an amendment is appropriate, please tell us why in your response.

After reviewing any amendment to your f iling and the information you provide in
response to these comments, we may have additional comments.

Form 10 -K for the Year Ended September 30, 2011

Item 1. Business, page 1

1. We note your response to comment 1 in our letter dated March 20, 2012 and that
“specialty” refers to pharmaceutical products that treat complex diseases, such as cancer,
diabetes and multiple sclerosis.   Please confirm that in future filings you will further
clarify the definition of specialty as explained in your respo nse letter, including a brief
description of how management makes the determination to categorize a particular
product or service as specialty.   If you believe a specific industry definition does not
exist, consider addressing the degree to which incompara bility may exist among you and
other market participants.   In this regard, it is unclear, for example, how diseases are

Tim G. Guttman
AmerisourceBergen Corporation
April 18 , 2012
Page 2

 classified as “complex” as opposed to non -complex or whether high cost is a determining
factor.   Please provide draft disclosure.

Notes  to Consolidated Financial Statements, page 41

Note 14. Business Segment Information, page 63

2. We note your response to comment two of our letter dated March 20, 2012.   Please
expand your analysis to discuss your consideration of the actual historical and  projected
future differences between the operating income margins and sales trends of ABDC and
ABSG, including the three generic oncology drugs you initially excluded, to arrive at
your conclusion on the similarity of their economic characteristics.   Alternatively, tell us
why you  have excluded the impact of certain specialty generic product introductions from
ABSG in your analysis of the gross margins and sales trends of ABDC and ABSG and
cite the accounting guidance that you are relying upon for the excl usion of this
information.  Also provide us with the financial information reviewed by your CODM for
the quarter ended December 31, 2011 (reflecting the reduction to three operating
segments beginning in fiscal 2012) that was used to make decisions about r esource
allocations and assess performance.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain  that the filing includes the information the Securities Exchange Act of
1934 and all applicable  Exchange Act rules require.   Since the company and its management are
in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

You may contact Brian McAllister at (202) 551 -3341 or John Archfield  at (202) 551 -
3315  if you have questions regarding comments on the financial statements and related matters.
Please contact Adam Turk at (202) 551 -3657 or James Lopez at (202) 551 -3536
with any other questions.

Sincerely,

/s/Tia L. Jenkins

    Tia L. Jenkins
        Senior Assistant Chief Accountant
Office of Beverages, Apparel and
Mining