ICAHN PARTNERS LP
                          ICAHN PARTNERS MASTER FUND LP
                         HIGH RIVER LIMITED PARTNERSHIP
                                JANA PARTNERS LLC

                                                              March 10, 2005

VIA FEDERAL EXPRESS AND FACSIMILE
----------------------------------
Mr. Luke R. Corbett
Chairman and Chief Executive Officer
Kerr-McGee Corporation
123 Robert S. Kerr Avenue
Oklahoma City, Oklahoma 73102

Dear Mr. Corbett:

         We are writing in response to the March 8th  announcement by Kerr-McGee
Corporation  ("KMG") regarding the board's decision to approve the sale of KMG's
chemicals business and the repurchase of $1 billion of shares. We are encouraged
that KMG agrees  with our  position  with  respect to the sale of its  chemicals
business.  However,  the board did not address the  substance  of our proposal -
taking advantage of the significant  arbitrage  opportunity we outlined. We have
spoken  with  several  of KMG's  largest  shareholders,  and we found  that each
believes that:

o KMG should not miss the  opportunity to LOCK IN HIGH OIL PRICES;
o KMG should STOP WASTING MONEY ON HIGH-RISK EXPLORATION;  and
o KMG should RETURN MORE MONEY TO SHAREHOLDERS IMMEDIATELY.

         We  continue  to  believe  that  if KMG  were  to  consummate  the  VPP
transaction  described  in our March 3rd  letter,  it would  unlock  significant
shareholder value.  Furthermore,  contrary to KMG's  mischaracterization  of our
proposal,  we are not  seeking  "quick  cash."  As such,  given  current  market
conditions,  if KMG were to  consummate  the VPP  transaction  we  proposed  and
commence a tender offer (as opposed to an uncertain and open-ended buy back such
as that  approved by the board) to  repurchase  its shares at $90 per share,  WE
WOULD COMMIT NOT TO SELL OUR SHARES IN SUCH AN OFFER.

         KMG has expressed  concern that returning  capital to its  shareholders
would  limit its ability to conduct  exploratory  drilling  activities.  That is
exactly  our point - we believe  KMG can spend its money  much more  judiciously
than to continue  spending money on high-risk  exploration.  Extrapolating  from
your public filings, we see that KMG's 3-year historic average exploration costs
through  the drill  bit  (including  revisions)  are  approximately  $40 per boe
(excluding  Westport and other  acquisitions).  At its current  share price (and
assuming  a value  for the  chemicals  business  within  management's  estimated
range),  KMG now has the  opportunity  to repurchase  its own shares and thereby
repurchase its own reserves at between $11 and $12 per boe.

         We  believe  that  KMG has  destroyed  shareholder  value  through  its
exploratory  activities over the last three years. We do not seem to be alone in
our opinion. In addition to the several large KMG shareholders with whom we have
spoken,  Goldman Sachs,  in a research  report  released on March 7th, stated as
follows:

              "Our concern with  Kerr-McGee's  current E&P business
     model is that its  strategy  of  trying  to  offset  the steep
     declines  inherent in its mature,  short-lived  core E&P asset
     base  does  not  appear  to be a good  fit  with  a  high-risk
     deepwater exploration strategy. If allowed to continue, WE SEE
     A HIGH LIKELIHOOD THAT KERR-MCGEE  COULD SQUANDER THE BENEFITS
     OF HIGH OIL PRICES.  . . . We believe that the most attractive
     solution  would be for  Kerr-McGee  to  "produce  out" its E&P
     reserves.  Given our view that  Kerr-McGee's  E&P  business is
     capable  of  generating  substantial  cash  flow,  THE  KEY TO
     UNLOCKING  THE  VALUE  WOULD BE TO SPEND  MINIMAL  AMOUNTS  OF
     CAPEX,  ESSENTIALLY  DEPLETE OUT ITS RESERVES  OVER TIME,  AND
     RETURN  REMAINING  CASH  FLOWS  BACK TO THE  SHAREHOLDERS.  We
     believe Kerr-McGee could choose to take advantage of currently
     high  commodity  forward  prices  to  lock  in  value  for its
     reserves. "1 (emphasis added)

         KMG's board should be focused on maximizing value for its shareholders,
the  constituency to whom the board owes its fiduciary  duties.  We are dismayed
that KMG has  chosen to make  dismissive  public  statements  instead  of taking
seriously our proposal for enhancing shareholder value. To resort to meaningless
rhetoric is wasteful,  just as, unfortunately for shareholders,  we believe much
of KMG's  exploratory  drilling  activity  has been.  Although we believe that a
proxy fight would be a debilitating  exercise for all involved, if KMG continues
to ignore  what we believe is the obvious way to unlock  shareholder  value,  we
will press forward to seek to elect the undersigned to the board at the upcoming
annual meeting of shareholders.  Further,  if oil prices were to decline and KMG
were to miss the significant  and unique  arbitrage  opportunity  that currently
exists,  management  and the board  will be  responsible  for  having  destroyed
shareholder value.

                                                     Very truly yours,

                                                     CARL C. ICAHN

                                                     BARRY ROSENSTEIN


SECURITY  HOLDERS ARE ADVISED TO READ THE PROXY  STATEMENT  AND OTHER  DOCUMENTS
RELATED TO  SOLICITATION OF PROXIES BY MESSRS.  CARL ICAHN AND BARRY  ROSENSTEIN
AND THEIR RESPECTIVE AFFILIATES FROM THE STOCKHOLDERS OF KERR-MCGEE  CORPORATION
FOR USE AT ITS ANNUAL  MEETING WHEN AND IF THEY BECOME  AVAILABLE,  BECAUSE THEY
WILL  CONTAIN  IMPORTANT  INFORMATION,  INCLUDING  INFORMATION  RELATING  TO THE
PARTICIPANTS IN ANY SUCH PROXY  SOLICITATION.  WHEN AND IF COMPLETED,  THE PROXY
STATEMENT  AND SUCH  OTHER  DOCUMENTS  WILL BE  AVAILABLE  AT NO  CHARGE  AT THE
SECURITIES  AND  EXCHANGE  COMMISSION'S  WEBSITE  AT  HTTP://WWW.SEC.GOV,  AND A
DEFINITIVE PROXY STATEMENT AND A FORM OF PROXY WILL BE MAILED TO STOCKHOLDERS OF
KERR-MCGEE CORPORATION.

--------
1 We have not  received,  nor have we sought,  permission  from Goldman Sachs to
publish excerpts from this research report.