Additional Information

Schlumberger has filed with the SEC a registration statement on Form S-4 containing a definitive proxy statement/prospectus of Schlumberger and Smith and other documents related to the proposed transaction. The registration has been declared effective by the SEC and Smith intends to mail the proxy statement/prospectus to its stockholders on or about July 27, 2010. STOCKHOLDERS ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT/PROSPECTUS AND REGISTRATION STATEMENT REGARDING THE PROPOSED TRANSACTION BECAUSE IT CONTAINS IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION, INCLUDING DETAILED RISK FACTORS. These documents contain important information about the proposed transaction that should be read carefully before any decision is made with respect to the proposed transaction. These materials are available to the shareholders of Smith at no expense to them. Investors and security holders can obtain the documents free of charge at the SEC’s web site, www.sec.gov. In addition, such materials (and all other documents filed with the SEC) are available free of charge at www.smith.com or www.slb.com. You may also read and copy any reports, statements and other information filed by Smith or Schlumberger with the SEC at the SEC public reference room at 100 F Street N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at (800) 732-0330 or visit the SEC’s website for further information on its public reference room.

Each company’s directors and executive officers and other persons may be deemed, under SEC rules, to be participants in the solicitation of proxies in connection with the proposed transaction. Information regarding Schlumberger’s directors and officers can be found in its proxy statement filed with the SEC on March 4, 2010 and information regarding Smith’s directors and officers can be found in its amendment to its annual report on Form 10-K filed with the SEC on April 30, 2010. Additional information regarding the participants in the proxy solicitation and a description of their direct and indirect interests in the transaction, by security holdings or otherwise, are contained in the definitive proxy statement/prospectus and other relevant materials.