U.S. Securities and Exchange Commission
                              Washington, DC 20549

                          NOTICE OF EXEMPT SOLICITATION

1. Name of the Registrant: Charles River Laboratories International, Inc.

2. Name of person relying on exemption: JANA Partners LLC

3. Address of person relying on exemption: 767 Fifth Avenue, 8th Floor, New
York, New York 10153

4. Written materials. Attach written material required to be submitted pursuant
to Rule 14a-6(g)(1)

June 16, 2010

Mr. James C. Foster
Chairman, President and Chief Executive Officer
Charles River Laboratories International, Inc.
251 Ballardvale Street
Wilmington, Massachusetts 01887


Mr. Foster,

     We  continue  to  believe  based on the  high  cost,  significant  risk and
inopportune  timing of the proposed  acquisition  by Charles River  Laboratories
International,  Inc.  ("Charles  River"  or the  "Company")  of WuXi  PharmaTech
(Cayman) Inc. ("WuXi") that this is the wrong path for your shareholders.  Based
on numerous  conversations after sending our June 7, 2010 letter, we also remain
convinced that shareholders will not support this transaction and note that even
at  this  early  stage  one  analyst  estimates  that  approximately  35% of the
shareholder  base is  already  opposed  to the  transaction  and  cites  none in
support.(1)  This is not surprising  given  continued  skepticism  regarding the
transaction,  including  analyst  commentary  yesterday  that "[WuXi]  stands to
benefit from this transaction more than [Charles River]" and estimating that the
transaction  would reduce the Company's value by  approximately $4 per share.(2)
After  reviewing  your June 14, 2010 letter,  we see no reason why this negative
shareholder sentiment should change.

       You have first  sought to justify the proposed  transaction  by asserting
that it would improve the Company's growth rates and margins. However, it should
surprise no one to learn that if Charles  River  acquires a company  with higher
growth and margins it will improve its own growth and margins, and these metrics
in a vacuum say nothing  about  whether this  investment  on the proposed  terms
generates  increased  shareholder  value.  If  Charles  River  shareholders  are
attracted to WuXi's growth and margins  (despite recent declines in both as WuXi
faces increased competition and wage inflation), they are free to invest in WuXi
directly or any other  company  with higher  growth and  margins,  and can do so
without  paying the  substantial  premium  Charles  River  proposes  to pay WuXi

       The real question of course is whether this  acquisition  would  generate
any definable  incremental value for Charles River shareholders  outside of what
they could  generate  simply by acquiring  WuXi stock directly on their own, and
here we believe your argument falls well short. Given the minimal cost synergies
of the proposed  transaction,

(1) "Charles  River  Laboratories  - Takeaways  from  Jefferies 2010 Global Life
Sciences Conference"; Dave Windley; Jefferies & Company, Inc., June 11, 2010.
(2) "CRL: Argument for WX completion continues to evolve; does management intend
to change  the terms and avoid  vote?";  Stephen  Unger,  William  Hite;  Lazard
Capital Markets, June 15, 2010.

the only real potential  incremental  benefit to  shareholders  would be revenue
synergies. However, management has not quantified such synergies, nor we believe
could they,  meaning it is impossible for Charles River  shareholders to ascribe
value to them.

       This is not surprising given that such synergies are speculative at best.
Large  customers  outside  of China  are not  typically  suited to  purchase  an
integrated  offering of chemistry and biology  services given their often highly
decentralized  purchasing  processes,  which are divided in some companies among
various  executives  based  upon the  phase  of the  process,  subspecialty  and
division. In addition, many compounds never leave the medicinal chemistry phase,
raising  further  doubts  about the  benefits  of a combined  offering.  We also
continue  to  believe  that any  customers  who might be able to  conform  their
processes to take  advantage  of a combined  offering  would likely  demand cost
concessions for doing so, creating the risk that any potential  integrated sales
come at the risk of losing pricing power. In addition, WuXi is well known in the
industry and thus it is unlikely that a combination would result in a measurable
increase in sales.  As recently  as  yesterday  another  analyst  noted  similar

         Management  has cited  recent  conversations  with major  customers  in
         support of the  transaction,  noting  that the  combination  will solve
         major  problems  for these  customers.  Outside of the cheaper  cost of
         outsourcing  relative  to the  use of  internal  staff,  we are  having
         trouble  understanding  the specifics of these problems,  and we wonder
         whether a joint  marketing  agreement (or some other  partnership  with
         [WuXi]) would be sufficient to satisfy the needs of these customers.(3)

       There is also again significant integration risk and we believe that your
comments  about  the  highly  distinct  geographies  and  operations  of the two
companies,  while  certainly  true,  miss the  point.  No one  expects  that the
Company's  biologists  will be asked to perform the functions of WuXi's chemists
or vice versa. However, as we discussed in our previous letter, for the proposed
transaction to deliver value the companies  must  successfully  integrate  their
selling  efforts,  and we see nothing in the Company's response which
addresses this.

     By asking shareholders to take a leap of faith with respect to the promised
benefits and its ability to overcome  integration  risks,  management  is asking
them to ignore  its prior  acquisition  history  and poor  record in  allocating
capital.  As we noted in our prior letter,  despite  numerous  acquisitions  and
significant  expenditures  on new  facilities  over the years,  the  Company has
significantly  and  consistently  underperformed  peers,  and the Company's last
major "transformational"  acquisition of Inveresk Research Group was followed by
continued stock underperformance and nearly a billion dollars in write-downs and
losses,  casting  doubt on  management's  ability to predict where the market is
heading. In addition, while the Company claims in its response that by proposing
this acquisition now it is "ensuring it has the best partner to capture this

(3) "CRL: Argument for WX completion continues to evolve; does management intend
to  change  the  terms and avoid  vote?";  Stephen Unger,  William Hite;  Lazard
Capital Markets, June 15, 2010.

accelerating  opportunity,"  we note again that by management's
own admission there are no alternate  buyers for WuXi,  meaning this opportunity
is in no danger of slipping away.

     Even  leaving  aside  whether  such  speculative  benefits  can in  fact be
realized, we see nothing in the Company's response that justifies the high price
of the contemplated  acquisition.  In fact,  focusing on the purchase price as a
multiple  to EPS instead of EBITDA as you suggest in your letter (to account for
WuXi's lower effective tax rate) only  underscores  that Charles River is paying
an  unjustifiably  high  price  for  WuXi.  Simply  accounting  for the tax rate
differential  provides an incomplete and misleading  picture (even leaving aside
that WuXi's lower  effective tax rate stems from current  government  incentives
which might not be available in the future,  meaning  WuXi's  effective tax rate
would be the 25% Chinese  statutory  rate,  similar to Charles  Rivers'  current
effective  tax rate.) As set forth in Exhibit A, if earnings  are also  properly
adjusted for annual stock  compensation  expense  (which is not accounted for in
WuXi's EPS estimates but is factored  into the Company's EPS  estimates)  WuXi's
EPS would be reduced by  approximately  $0.12,  implying a 2010 P/E  multiple of
28.8x.  Furthermore,  WuXi's cash outflows for capital  expenditures in 2010 are
estimated to be  substantially  higher than the expense  impact in  depreciation
(with the  opposite  being true for the  Company as it  harvests  the  extensive
capital  investments of the past few years).  As further set forth in Exhibit A,
adjusting for this difference in cash outflows for capital  expenditures as well
results in an implied  2010  multiple  for WuXi of 56.2x,  more than  double the
24.7x  multiple  cited in your letter,  versus a mid-teens  multiple for Charles
River analyzed on a comparable basis.(4)

     This extreme  valuation  differential  again  underscores  the  substantial
shareholder  value which could be  generated  from a large share  repurchase  as
outlined in our  previous  letter.  As you stated at the  Jefferies  Global Life
Sciences   Conference  last  week,  the  Company  estimates  that  the  proposed
acquisition  would reach mid-teens  returns in year five, an assumption which we
have noted is based on aggressive WuXi growth assumptions. However, based on the
Company's  own  standalone  multi-year  projections,  a share  repurchase of its
undervalued  stock would generate  higher returns with none of the strategic and
integration risks described above. For example,  the approximately 14% accretion
to 2011 EPS which we estimated in our previous letter would be generated at that
time by a  repurchase  of  approximately  19% of the  Company's  stock  at a 10%
premium would be delivered immediately and would grow thereafter.  A sale of the
Company may also deliver  substantially  greater value without the strategic and
integration risk described above,  another avenue which we have noted appears to
be potentially available.

     Despite our strong objections, we are pleased that it appears based on your
response letter and your televised  appearance yesterday that you have committed
to  attempting  to make a case on the merits to  shareholders  for the  proposed
acquisition.  We believe  any  effort to make an end run around the  shareholder
approval  process,  as some have speculated the Company might attempt,  would be
uniformly condemned and that shareholders would not hesitate


(4) We note your reliance on the multiple of P/E to growth estimates  ("PEG") in
your response  letter.  However we are unaware of any analyst who relies on that
metric to value Charles River or WuXi. We also believe it would not be useful to
do so given wide ranging  growth  forecasts  based on  inconsistent  time frames
including LTM growth in earnings  (which would not capture future  growth),  NTM
growth in earnings  and  projections  for  multi-year  growth in  earnings.  Not
surprisingly,  analyst estimates for Charles River's long-term growth rate range
from 8% to 26% per Bloomberg,  which would result in a PEG range from below 1.0x
to above 2.0x.

early next year to replace a board that sought to  consummate  this  transaction
over  their  objections.  While  we were  disappointed  that  you  canceled  our
scheduled  call on Monday to discuss these matters  further and we were not able
to  address  these  points  with  you  directly,  we  remain  available  at your
convenience and can be reached at (212) 455-0900.


/s/ Barry Rosenstein
Barry Rosenstein
JANA Partners LLC
Managing Partner


Quotation of analysts  herein does not  necessarily  indicate that such analysts
support the views expressed herein.

                                    EXHIBIT A

------------------------------------------------- ---------- ------------
------------------------------------- ----------- ---------- ------------
EPS (1)                                                            $0.86

   Depreciation expense (1)                                          $24
   Capital expenditures (2)                                         (55)
   Stock compensation expense (1)                                   (11)
Net pre-tax adjustment                                             ($42)

Tax rate (3)                                                         14%

After-tax adjustment                                               ($36)

Diluted shares outstanding (MM)                                      74

Per share adjustment                                             ($0.48)
"ADJUSTED EPS"                                                    $0.38

PRICE / EPS @ $21.25 TRANSACTION PRICE                            24.7X
PRICE / ADJUSTED EPS @ $21.25 TRANSACTION PRICE                   56.2X
(1) Estimates per Bank of America Merrill Lynch research as of March 9, 2010.
EPS estimates in-line with consensus as of deal announcement.
(2) Per midpoint of WuXi guidance in 4Q 2009 earnings release.
(3) Per midpoint of 2010 WuXi tax rate guidance in 4Q 2009 earnings release.