A lawsuit filed in federal court last week alleges that billionaire William Koch, a major supporter of Republican presidential candidate Mitt Romney and brother to the infamous tea party financiers Charles and David Koch, kidnapped and held captive a long-serving former executive at Oxbow Carbon & Minerals Inc., interrogating him about his concerns over the company's tax avoidance scheme.

Koch denied any wrongdoing last weekend through a prepared statement issued on Oxbow's website, which alleged that the plaintiff, former Oxbow Senior Vice President Kirby Martensen, was part of a scheme to defraud the company of more than $40 million.

The complaint alleges that Koch directed a massive review of internal communications after receiving an anonymous letter in 2011 that accused Martensen and others of various crimes, including theft. "Based on this surreptitious review of plaintiff's emails and voice communications Koch learned that Martensen and others expressed concern of the legality of what they were doing on behalf of Oxbow and their distrust of upper management," the lawsuit explains, according to excerpts published by Courthouse News. "As a result, William Koch promoted and implemented a plan to intimidate and discredit plaintiff for the purpose of chilling his speech and damaging his credibility."

Martensen's lawsuit adds that he was tricked into visiting Koch's Colorado ranch in March, where he was interrogated by two "agents of Koch" before being given termination papers. The complaint goes on to allege that Martinsen was sent to a cabin on the property and held there for several hours before a driver and an escort ushered him to a small airport in Denver, despite his requests to be taken to Aspen to catch a previously-booked flight to San Francisco. Once in Denver, he claims that Koch agents forced him to get on an airplane that took him to Oakland, where a car was already waiting to take him to a pre-determined hotel. At that point, Martensen's suit says he alerted an airport employee, who called him a taxi instead.

The complaint goes on to say that he believed several of the Koch agents were armed, causing him significant distress and anxiety throughout the two-day ordeal.

"Kirby Martensen states in a lawsuit that we investigated him for participating in a wide-ranging scheme to defraud, accepting bribes and diverting business from our company," a statement on the Oxbow website reads. "He is right. We absolutely investigated Martensen and determined that he did participate in the fraud against the company." The company added that "several of the wrongdoers" have since implicated Martensen in their scheme.

Koch founded Oxbow in the 1980s, shortly after parting ways with Koch Industries. Since then, he's amassed a wealth of $4 billion, according to Forbes -- which only amounts to about one-seventh of his brothers' combined wealth.


Illustration: Flickr user DonkeyHotey, creative commons licensed.