Corporate Information

Corporate Headquarters
5555 San Felipe Road
Houston, TX 77056-2723

Marathon Oil Corporation Web site:
www.marathon.com

Investor Relations Office
5555 San Felipe Road (77056-2723)
P.O. Box 3128 (77253-3128)
Houston, TX

Kenneth L. Matheny, Vice President, Investor Relations
  and Public Affairs
klmatheny@marathonoil.com
713-296-4114

Howard J. Thill, Manager, Director, Investor Relations
hjthill@marathonoil.com
713-296-4140

Notice of Annual Meeting
The 2004 Annual Meeting of Stockholders will be held in Houston, Texas, on April 28, 2004.

Independent Accountants
PricewaterhouseCoopers LLP
1201 Louisiana, Suite 2900
Houston, TX 77002-5678

Common Stock Exchange Listings
New York Stock Exchange (Principal Exchange)
Chicago Stock Exchange
Pacific Stock Exchange

Common Stock Symbol
MRO

Principal Stock Transfer Agent
National City Bank
Corporate Trust Operations
P.O. Box 92301
Cleveland, OH 44193-0900
888-843-5542 (Toll free)
216-257-8508 (Fax)

Annual Report on Form 10-K
Additional copies of the Marathon 2003 Annual Report may
be obtained by contacting:
Public Affairs
5555 San Felipe Road
Room 4150
Houston, TX 77056-2723
713-296-3911

Dividends
Dividends on Common Stock, as declared by the board of directors, are normally paid on the tenth day of March, June, September and December

Dividend Checks Not Received / Electronic Deposit
If you do not receive your dividend check on the appropriate payment date, we suggest you wait about 10 days after the payment date to allow for any delay in mail delivery. After that time, advise National City Bank by phone or in writing for a replacement check to be issued. You also may contact National City Bank to authorize direct electronic deposit of your dividends or interest into your bank account.
  Dividend Reinvestment and Direct Stock Purchase Plan
The Dividend Reinvestment and Direct Stock Purchase Plan provides stockholders with a convenient way to purchase additional shares of Marathon Oil Corporation Common Stock without payment of any brokerage fees or service charges through investment of cash dividends or through optional cash payments. Stockholders of record can request a copy of the Plan Prospectus and an authorization form from National City Bank. Beneficial holders should contact their brokers

Lost Stock Certificate

If a stock certificate is lost, stolen or destroyed, notify National City Bank in writing so that a stop transfer can be placed on the missing certificate. National City Bank will send you the necessary forms and instructions for obtaining a replacement certificate. You may be required to obtain and pay for the cost of an indemnity bond. If you find the missing certificate, notify National City Bank in writing immediately so that the stop transfer can be removed. To avoid loss, theft or destruction, we recommend that you keep your certificates in a safe place, such as a safe deposit box at your bank.

Taxpayer Identification Number
Federal law requires that each stockholder provide a certified Taxpayer Identification Number (TIN) for his/her stockholder account. For individual stockholders, your TIN is your Social Security Number. If you do not provide a certified TIN, Marathon may be required to withhold 28 percent for federal income taxes from your dividends.

Address Change
It is important that you notify National City Bank immediately, by phone, in writing or by fax, when you change your address. As a convenience, you also may indicate an address change on the face of your quarterly dividend check. Seasonal addresses can be entered for your account

Exchange of Certificate
If you have not done so, we recommend you return any USX Corporation or United States Steel Corporation common stock certificates which were issued prior to May 7, 1991, in exchange for certificates for Marathon Oil Corporation Common Stock. Certificates should be sent to National City Bank.

Range of Marathon Stock Sale Prices and Dividends
      2003    
  Quarter   High   Low   Dividend
  First   $ 24.04   $ 20.20   $ .23
  Second   $ 27.00   $ 22.56   $ .23
  Third   $ 29.42   $ 25.01   $ .25
  Fourth   $ 33.37   $ 28.91   $ .25
  Year   $ 33.37   $ 20.20   $ .96