In response, American investor Paul Singer's firm, Elliott Associates, and other hedge funds, which together owned about $700 million of Vitro's old debt, claimed that Martínez had helped Vitro "muscle investors out of hundreds of millions of dollars through financial sleight of hand," and accused Vitro of "audacity, brazen manipulation and greed." Singer and the hedge funds sued Vitro and Fintech in the U.S., where a Dallas court ruled in their favor in summer 2012. An appellate court trial began in October.