Schlumberger N.V. (NYSE:SLB) Director Michael E. Marks purchased 8,000 shares of Schlumberger N.V. stock in a transaction on Friday, August 11th. The shares were acquired at an average cost of $64.20 per share, for a total transaction of $513,600.00. The acquisition was disclosed in a document filed with the Securities & Exchange Commission, which is available at this link.