[Editor's note: This article has been updated to reflect the court's ruling on September 10.]

On November 20, 2012, Rex Wempen sat on the witness stand in London's High Court. The former U.S. Army Green Beret was testifying in a $1.65 billion case that his company, Excalibur Ventures, had brought against a group of oil businesses. The dispute stemmed from a soured oil exploration deal in Kurdistan that Excalibur had signed with a company called Texas Keystone Inc. While the trial was essentially about a business deal, a secondary theme arose during the litigation: How could Excalibur, which had virtually no assets, afford to bring such a complicated and expensive case?