PROSPECTUS
SUPPLEMENT NO. 13
To
Prospectus dated August 9, 2006, as supplemented by the Prospectus
Supplement
No.
1 dated
September 8, 2006 and the Prospectus Supplement No. 6 dated January 18,
2007
Filed
Pursuant to Rule
424(b)(7)
Registration
File
No.
333-136450
$350,000,000
Charles
River Laboratories International, Inc.
2.25%
Convertible Senior Notes due 2013 and Common Stock Issuable Upon Conversion
of
the Notes
Interest
payable June 15 and December 15
This
prospectus
supplement supplements information contained in that certain prospectus
supplement No. 6 dated January 18, 2007 to the prospectus supplement No. 1
dated
September 8, 2006 to the prospectus dated August 9, 2006 of Charles River
Laboratories International, Inc., which we collectively refer to as the
“prospectus,” covering resale by selling securityholders of our 2.25%
Convertible Senior Notes due 2013 and common stock issuable upon conversion
of
the notes. This prospectus supplement is not complete without, and may not
be
delivered or utilized except in connection with, the prospectus, including
any
amendments or supplements thereto. The terms of the notes are set forth in
the
prospectus.
See
"Risk
Factors" beginning on page S-5 of the prospectus supplement No. 1 dated
September 8, 2006 for a discussion of certain risks that you should consider
in
connection with an investment in the notes or in shares of our common
stock.
Neither
the Securities and Exchange Commission, any state securities commission nor
any
other United States regulatory authority has approved or disapproved of these
securities or determined if this prospectus supplement or the prospectus is
truthful or complete. Any representation to the contrary is a
criminal offense.
The
date of this
prospectus supplement is September 17, 2007
The
table appearing under the section entitled “Selling Securityholders” on page S-2
of the prospectus supplement No. 6 dated January 18, 2007 is amended
by adding the following information below, which is based on information
received from the selling securityholders on or prior to September 16,
2007.
Name
|
Aggregate
Principal
Amount
of Notes
That
Are Owned and
May
Be
Sold
|
Percentage
of Notes
Outstanding
|
Number
of Shares of Common Stock
that
May Be Sold1
|
Percentage
of Common Stock Outstanding2
|
McMahan
Securities Co. L.P.3
|
$ 884,000
|
*
|
18,063
|
*
|
*
Less than one percent (1%)
(1) Assumes
conversion of all
of the holder’s notes at a conversion rate of 20.4337 shares of common
stock per $1,000 principal amount of notes. This conversion rate is
subject to adjustment, however, as described under “Description of
Notes—Conversion rights.” As a result, the number of shares of common stock
issuable upon conversion of the notes may increase or decrease in the
future.
(2)
Calculated based on Rule 13d-3(d)(1)(i) of the Exchange Act, using 67,906,564
shares of common stock outstanding as of August 1, 2007. In calculating this amount
for each holder, we treated as outstanding the number of shares of common stock
issuable upon conversion of all of that holder’s notes, but we did not assume
conversion of any other holder’s notes.
(3)
This selling securityholder is a broker-dealer.
Information
about
other selling securityholders will be set forth in additional prospectus
supplements, if required.