SecProbe.io

<DOCUMENT>
<TYPE>LETTER
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>

Via Facsimile and U.S. Mail
Mail Stop 03-09

April 26, 2005

Mr. Alan I Edrick
Executive Vice President and
Chief Financial Officer
Biosource International, Inc.
542 Flynn Road
Camarillo, CA  93012

Re:	Biosource International, Inc.
	Form 10-K for the fiscal year ended December 31, 2004
	File No. 0-21930

Dear Mr. Edrick:

We have reviewed your filing and have the following comments.  We
have limited our review of the above referenced filing to only
those
issues addressed. In our comments, we ask you to provide us with
supplemental information so we may better understand your
disclosure.
Please provide us the supplemental information requested within 10
business days of the date of this letter or tell us when you will
provide a response prior to the expiration of the 10-day period.
Please furnish a letter with your supplemental responses that keys
your responses to our comments.  Detailed letters greatly
facilitate
our review.  You should file the letter on EDGAR under the form
type
label CORRESP.  Please understand that we may have additional
comments after reviewing your responses to our comment.

	Please understand that the purpose of our review process is
to
assist you in your compliance with the applicable disclosure
requirements and to enhance the overall disclosure in your filing.
We look forward to working with you in these respects.  We welcome
any questions you may have about our comments or on any other
aspect
of our review.  Feel free to call us at the telephone numbers
listed
at the end of this letter.

Form 10-K for the fiscal year ended December 31, 2004

Management`s Discussion and Analysis of Financial Condition and
Results of Operations

Critical Accounting Policies

Allowance for Inventory, pg. 17

1. We noted your accounting policy regarding your reserve for 100%
of
the costs of manufactured antibody inventory.  Please explain to
us
management`s basis for this policy and how it complies with GAAP,
specifically Chapter 4 of ARB 43. Regarding this inventory to help
us
understand the effect of this estimate on your financial
statements,
please provide us a roll forward of the reserve from January 1,
2002
through December 31, 2004 showing the amount you charged to
operations for each period in recording the reserve and the amount
and nature of any other adjustments. Also provide us a schedule
that
shows the revenue and cost of sales related to this inventory that
you recorded during each period.  Finally, tell us where in the
filing you provided information similar to that in the roll
forward
and for the revenue and cost of sales so that an investor can
understand the effects of recording antibody inventory at a zero
cost.

Liquidity and Capital Resources, pages 21-22

2. Please provide us an analysis of explaining the period to
period
changes in cash flows from operating activities to enable us to
understand the underlying reasons for period to period
fluctuations
as opposed to a discussion of a)the changes in the adjustments to
reconcile net income (loss) to net cash provided by operating
activities and b)changes in operating assets and liabilities.
Please
refer to Section IV of the Securities and Exchange Commission`s
Guidance Regarding Management`s Discussion and Analysis of
Financial
Conditions and Results of Operations (Release Nos. 33-8350; 34-
48960;
FR-72). Please tell us why you did not include this analysis in
your
filing or where in your filing you accomplish this objective.

*    *    *    *

	We urge all persons who are responsible for the accuracy and
adequacy of the disclosure in the filings reviewed by the staff to
be
certain that they have provided all information investors 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.

	In connection with responding to our comments, please
provide,
in writing, a statement from the company acknowledging that

* the company is responsible for the adequacy and accuracy of the
disclosure in the filings;
* staff comments or changes to disclosure in response to staff
comments in the filings reviewed by the staff do not foreclose the
Commission from taking any action with respect to the filing; and
* the company may not assert staff comments as a defense in any
proceeding initiated by the Commission or any person under the
federal securities laws of the United States.

	In addition, please be advised that the Division of
Enforcement
has access to all information you provide to the staff of the
Division of Corporation Finance in our review of your filing or in
response to our comments on your filing.

      You may contact Todd Sherman, staff accountant, at 202-824-
5358
or Kevin Woody, Branch Chief, at 202-942-7332, if you have
questions
regarding the comments. In this regard, do not hesitate to contact
me, at (202) 942-1803.

								Sincerely,

								Jim B. Rosenberg
								Senior Assistant Chief
Accountant
??

??

??

??

Alan I. Edrick
Biosource International, Inc.
Page 3

</TEXT>
</DOCUMENT>