Koch Sued by Executive Claiming He Was Held Captive

William Koch held a senior executive of his Oxbow energy company captive for almost two days after discovering his concerns about a plan to avoid U.S. taxes on $200 million in profit, the now ex-employee said in a lawsuit.

Former Oxbow Senior Vice President Kirby Martensen alleged that an unrelated company probe revealed his misgivings over the purported effort by Oxbow Carbon & Minerals LLC. As a result, Martensen said, he was falsely imprisoned by Koch’s agents and interrogated at a remote Colorado estate as part of an attempt to intimidate him. He was also fired, he said.