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 7, 2010

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


Mr. Foster,

     JANA Partners LLC ("JANA",  "we" or "us") beneficially owns more than 7% of
the  outstanding  shares  of  Charles  River  Laboratories  International,  Inc.
("Charles River" or the "Company") making us the Company's  largest  shareholder
based upon publicly available  information.  We acquired our position because we
believe  Charles  River is  currently  underappreciated  by the market given its
dominant position in the highly defensive research models market, its attractive
valuation on a standalone  basis, the expected  cyclical recovery in preclinical
services  and ongoing  positive  secular  trends in  pharmaceutical  and biotech
outsourcing.  We  appreciated  you  and  Dr.  Ge Li,  Chairman  and  CEO of WuXi
PharmaTech (Cayman) Inc. ("WuXi"),  taking the time to meet with us last week to
discuss the Company's  proposal to acquire WuXi. While we understand your stated
strategic  rationale,  we have serious  doubts about the wisdom of pursuing this
transaction at this time.  Even if the  contemplated  benefits can ultimately be
realized,  we believe  that the high  cost,  significant  integration  risks and
inopportune  timing  simply  make the  proposed  acquisition  the wrong path for
Charles River  shareholders.  For these  reasons,  we intend to vote against the
issuance of Company stock required to complete the proposed acquisition,  and we
believe  based on  shareholder  sentiment  it is likely  that a majority  of the
Company's shareholders will do the same.

     Despite WuXi's valuable assets and well-regarded  chemistry  operation,  we
believe the proposed price, equal to approximately 16x estimated  consensus 2010
EBITDA at  announcement  compared to  approximately  8x for Charles River on the
trading  day  prior  to the  announcement,  cannot  be  justified  given  WuXi's
declining  margins and falling growth rates.  WuXi's gross margins have declined
each year  since  2003 and WuXi  predicts  its gross  margin  will fall again in
2010.(1)  We  believe  these   persistent   margin   declines  are  due  to  the
commoditization of WuXi's core discovery  chemistry  business,  and evidence the
declining  opportunity for labor arbitrage in China.  WuXi's annual sales growth
rate  also  fell  each  year  from  2006  through   2009,   and  the   projected
reacceleration of future growth comes with significant added risk in the face of

(1)  Gross  profit  adjusted  for   amortization  of  intangibles.

growing  competition in its core chemistry  business and reliance on growth from
its fledgling toxicology business.

     Despite such trends, the Company's recently filed proxy materials show that
the Company and its  advisors  relied  upon what  appear to be  aggressive  WuXi
standalone  growth  and  margin   assumptions  in  evaluating  the  contemplated
acquisition  and in estimating that it would be neutral to earnings per share in
2011.  In fact,  analysts have pointed out that even WuXi's own 2010 guidance is
below the  projections  Charles River relied upon in formulating  its offer.  As
Jefferies & Co. analysts have noted, "We believe the credibility of the 2011 and
2012  estimates  is low  given  that 2010  estimates  are  extremely  aggressive
compared  to  [WuXi's]  own  guidance  issued  only three  weeks  ago."(2)  Such
assumptions  for WuXi are also  well  above  consensus,  and as Bank of  America
Merrill Lynch analysts have pointed out would "require  sustainable Lab services
growth  and  successful  execution  in two  relatively  early  stage  businesses
([toxicology] and  manufacturing)  while driving margin expansion in the face of
pricing pressure."(3)

     The proposed  acquisition  would also pose  significant  integration  risks
given the  challenges  of  integrating  a new business  line located  across the
globe. As Jefferies & Company analysts  recently  observed,  "Investors must bet
against history to believe that [Charles  River] can integrate  [WuXi] without a
stumble,  and at over 15x our 2010 EBITDA estimate,  [Charles River's] bet is an
expensive  one."(4) It is also  important  to note that to finance the  proposed
transaction  Charles  River  plans to assume  significant  additional  leverage,
raising its total debt to EBITDA ratio to 3.3x,  further  eroding its margin for
error in integrating the two businesses. In addition,  combining and integrating
a  broad  platform  of  discovery  and  preclinical  services  is a  significant
distraction at a time when other public contract research organizations ("CROs")
have been lowering  guidance and Charles  Rivers'  cyclically  weak  preclinical
business requires increased attention.

     The timing of the proposed  transaction is also highly  inopportune for the
Company's shareholders.  If this acquisition occurs now, WuXi shareholders would
walk away with a  significantly  larger  portion of the pro forma entity than if
the proposed  transaction  occurred after the anticipated cyclical recovery when
Charles  River shares should  recover  their value.  While WuXi may benefit from
related cyclical trends as well,  discovery  services have not suffered declines
as severe as  preclinical  services like  toxicology.  In any case, as described
above  Charles  River  has also  already  factored  in  aggressive  WuXi  growth
assumptions  in its valuation.  Finally with respect to timing,  as disclosed in
the Company's proxy  materials there appear to be no alternate  buyers for WuXi,
which casts doubt not only on the premium value ascribed to WuXi but also on

(2) "Putting on its Marketing  Hat",  David  Windley,  Timothy C. Evans,  Andrew
Hilgenbrink,  Ph.D.;  Jefferies  & Company,  Inc.,  June 2, 2010.
(3) "Merger  assumptions  leave little room for error";  Eric Lo, Eric H. Chang,
Bank of America Merrill Lynch, June 2, 2010.
(4) "Putting on its Marketing  Hat";  David  Windley,  Timothy C. Evans,  Andrew
Hilgenbrink, Ph.D.; Jefferies & Company, Inc., June 2, 2010.

why this  transaction is necessary now given that there is little risk of losing
WuXi to a competitive bidder.

     Charles  River's share price  performance in recent years  underscores  the
danger for  shareholders of inefficient  capital  allocation.  Despite  numerous
acquisitions and significant expenditures on new facilities (which in some cases
have been  temporarily  closed  shortly after  completion)  over the years,  the
Company has significantly and consistently underperformed peers.(5) For example,
in 2004 the Company acquired Inveresk Research Group ("Inveresk"), another large
transaction which like WuXi was hailed as a  "transformational"  acquisition and
was intended to provide a "broader strategic  platform for growth."(6)  However,
from the trading day before the Inveresk  acquisition  was  announced  until the
trading day before announcement of the proposed WuXi transaction,  the Company's
shares declined  approximately  19%, compared to an average increase of 108% for
its  comparably-sized  industry  peers.(7)  After failing to realize the goal of
combining  early and late  stage CRO  services,  the  Company  soon  divested  a
significant  portion of the assets  acquired  in the  Inveresk  transaction  and
incurred  hundreds of millions  of dollars in combined  write-downs  and losses.
While  smaller  tuck-in  acquisitions  have  been more  successful,  as RW Baird
recently noted,  "Past  acquisitions  haven't been [the Company's] strong point,
nor have the majority panned out across the industry."(8)

     While  we grasp  the  theory,  we  believe  that in  reality  the  promised
strategic  benefits of the  contemplated  transaction  are also far from certain
enough to justify the proposed price and timing. As one analyst has noted:

     "We still see the valuation premium applied as aggressive and the rationale
     for combination lacking enough supporting evidence to assuage all concerns.
     We  do   believe   that  the   combined   entity   will  be   competitively
     differentiated,   but  we're   unconvinced   that  it  will  be  materially
     competitively  advantaged.  We think  China is an exciting  market,  and we
     believe that a larger  presence  there is a long-term  positive,  yet we're
     unsure of [Charles  River's] ability to find synergies  between

(5) For the one,  three and five year periods ending on the trading day prior to
the  announcement of the WuXi  acquisition,  the Company's  shares have returned
approximately 57%, (17)% and (17)%, respectively, compared to 106%, 8% and 110%,
respectively, on average  for  comparably-sized  industry  peers  Covance  Inc.,
Parexel  International  Corp., ICON plc and Pharmaceutical  Product  Development
Inc., and 46%, (12)% and 17%, respectively,  for the S&P 500.  All  calculations
assume reinvestment of dividends.
(6) Charles River presentation prepared for joint conference call with Inveresk,
July 1, 2004.
(7) Such industry peers consist of Covance Inc.,  Parexel  International  Corp.,
ICON  plc  and  Pharmaceutical   Product  Development  Inc.  The  S&P  500  also
outperformed the Company,  returning  approximately 20%, during the same period.
All calculations assume reinvestment of dividends.
(8) Charles River  Laboratories";  Eric W. Coldwell,  Nicholas Juhle;  Robert W.
Baird & Co.,  May  12,  2010.  Analysts  such as UBS  Investment  Research  have
expressed  similar  doubts,  noting that "given Charles  River's mixed M&A track
record  (especially  the  difficulties  with the Inveresk  acquisition)  and the
complexity of the WuXi transaction as it relates to combining different business
models and corporate  cultures,  we believe the  integration and execution risks
are above  average."  "A Closer Look at the WuXi  Acquisition";  Derik de Bruin,
Ph.D., Daniel Arlas, Rafael Tejada; UBS Investment Research, May 13, 2010.

     the eastern chemistry/manufacturing footprint of [WuXi] and its own western
     biology business."(9)

     More broadly,  we believe that combining discovery chemistry and biology to
create revenue  synergies is an untested  proposition  and may not mesh with how
customers  currently  purchase these services,  which at least in some cases are
done on a  decentralized  basis.  The Company  relies upon a large  global sales
force with multiple points of customer contact working within a highly regulated
framework,  making the  generation of sales  synergies  from a combination  with
WuXi's sales force highly uncertain. It is also worth noting that WuXi is not an
unknown provider to  pharmaceutical  and biotech  customers seeking to outsource
drug  discovery,   also  casting  uncertainty  on  whether  significant  revenue
synergies can be obtained by a  combination.  In addition,  management's  stated
intention to leave WuXi's ERP system in place for the foreseeable  future (until
it can  complete  its own new ERP systems  implementation),  rather than rapidly
migrating  them to the Company's own systems,  will likely make sales  synergies
more  difficult  to  achieve  as  pricing  a  bundled   offering  will  be  more
challenging.  Another concern with respect to the proposed  strategy is that new
and existing customers may demand lower prices for a combined offering,  meaning
that any potential revenue synergies could be eroded by deterioration in pricing
power on the larger  components of the combined  offering.  Such pricing erosion
could be  exacerbated  by the  divergent  pricing  models of  Charles  River and

     Simply  put,   we  believe   that  there  are  much  more   promising   and
straightforward  means at present to create  shareholder  value than acquiring a
company with decelerating growth prospects and significant  integration risks at
an expensive valuation using a large amount of the Company's  undervalued stock.
For example, we note that the Company could employ the same multiple of leverage
to  trailing  EBITDA  it  would  assume  in a  WuXi  acquisition  to  repurchase
approximately  19% of its  currently  undervalued  outstanding  shares  at a 10%
premium to the current Charles River share price,  without any integration risk.
We believe that a share  repurchase of this magnitude  would result in accretion
to 2011  earnings per share of  approximately  14%, and growing  thereafter.(11)
Based on its history as a leveraged  buyout,  robust private equity  activity in
the  CRO  space  and  recent  published  reports,  we  believe  there  could  be
significant private equity interest in the Company, creating potentially

(9) "Charles River  Laboratories";  Eric W. Coldwell,  Nicholas Juhle; Robert W.
Baird & Co., May 12, 2010."
(10) Bank of America Merrill Lynch for example has expressed  concerns regarding
"potential cannibalization of sales from having a different pricing model in the
US/EU vs. Asia." "Merger assumptions leave little room for error"; Eric Lo, Eric
H. Chang; Bank of America Merrill Lynch, June 2, 2010.
(11) For purposes of our share  repurchase  analysis we have made the  following
assumptions:  1) a share  repurchase  price of $36.26 (a 10%  premium to Charles
River's  June  4,  2010  closing  price  of  $32.96);  2)  66.2  million  shares
outstanding  as of April  15,  2010 per  Charles  River's most  recent  10-Q; 3)
standalone  2011  non-GAAP EPS of $2.70 based on Company  guidance for pro forma
earnings  and  expected  neutral  impact to 2011  earnings  from  proposed  WuXi
transaction;  4)  total  leverage  of  3.3x  trailing  standalone  EBITDA  and a
borrowing  cost of 4.5%  (consistent  with leverage  level and borrowing rate of
proposed  WuXi  transaction);  5)  termination  fee of $25 million  (pursuant to
acquisition   agreement   following   Company   shareholder   rejection  of  the
transaction)  paid out of excess cash with foregone interest of 1%; and 6) a tax
rate on incremental debt and foregone cash interest of 35%.

another  means  of  realizing  maximum  shareholder  value  without  significant
operating or integration risk.

     Not surprisingly in light of these facts,  many Charles River  shareholders
have  already  expressed  their  displeasure  with the proposed  acquisition  by
disposing of their stock,  which  contributed to a share price decline of almost
16% the day the proposed deal was announced.  We believe that sentiment  among a
significant  percentage of current shareholders is also decidedly  negative.(12)
If as appears  likely  the  Company's  shareholders  reject  the  proposed  WuXi
acquisition,  we believe the Company is  well-positioned  for the future and has
several  attractive options for pursuing future value creation for shareholders,
and we are prepared to assist  management in exploring such options if we can be
of any assistance.  In the meantime,  we can be reached at (212) 455-0900 should
you wish to discuss any of these matters further.


/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.

(12) For example,  RW Baird noted that "we know that there is a large contingent
of  shareholders  unhappy  with the  valuation  and  strategy."  "Charles  River
Laboratories";  Eric W. Coldwell, Nicholas Juhle; Robert W. Baird & Co., May 12,
2010.  Wells Fargo  reported  that,  "We fielded  multiple  calls from investors
regarding the deal, and most of them expressed a general  disdain." "CRL:  Final
Thoughts  on Q1 2010 And WX Deal";  Greg T.  Bolan,  Eric  Hebert;  Wells  Fargo
Securities, April 26, 2010.