the easiest way to check is to email them from a ‘junk mail’ email address and ask them for a job description for a specific job. They have none so they will BS you a bit and re-ask you for your info and CV.

Or, you can make up one and send it in.. even if you send in Jeffery Dahlmer’s and ask for a job in the cooking department you will get accepted and a request for a fee will follow.

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They even have a fraud warning on their site about scammers using their name
http://careers.slb.com/fraud.aspx
"There are a few quick ways to recognize fraud:

1. Schlumberger emails always end in "@slb.com". Any email styled with "Schlumberger" using a different format is not genuine. Schlumberger will NEVER request a prospective applicant to email information to an email address not ending in "@slb.com".
2. Schlumberger website pages always include http://www.slb.com. Any other format is not genuine. Schlumberger will NEVER request a prospective applicant to visit a website with any address that does not include http://www.slb.com.
3. Prior to employment offers, prospective employees are ALWAYS invited to an interview with Schlumberger personnel.
4. The location of the interview is ALWAYS provided to candidates either by phone, or e-mail from a Schlumberger email account ending in "@slb.com".
5. No money transfers or payments of any kind will EVER be requested by Schlumberger as part of the recruitment process; or for immigration documents, insurance, or any other purpose.
6. No job offers will be made prior to a formal interview process from Schlumberger.

Should you experience any of the foregoing, please treat the communication as fraudulent and forward it to: Report-Job-Scam@slb.com. Schlumberger will strive to investigate the situation and have corrective action taken. "

Report the email you got to the real company and be sure to tell them exactly where you found the job posting
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