Schlumberger Ltd. has sold its interest in...

Schlumberger Ltd. has sold its interest in National Semiconductor Corp. back to the Santa Clara, Calif.-based company for $127 million, according to a filing with the Securities and Exchange Commission. The New York-based oil-field services firm gained the stake in National Semiconductor when it sold its Fairchild Semiconductor unit to National Semiconductor last year. In effect, the buyback turns the Fairchild deal into a cash transaction instead of a stock deal.