Two months before Mt. Gox filed for bankruptcy it was sued by a customer seeking the return of funds in a case that highlights some of the red flags raised in the run-up to the collapse of what was once the world's biggest bitcoin exchange, Reuters reported. New York resident Marko Simovic filed a civil action at the Tokyo District Court on Dec. 24, seeking to recover $105,000 he had on deposit at Mt. Gox and about $14,000 in interest, court filings show. Simovic, who described himself as a software developer who previously managed the bitcoin operations for a hedge fund, said Mt. Gox dodged repeated requests to withdraw funds from his account, which as of July 1 was credited with $935,000 in cash. Simovic could not be reached for comment. Mt. Gox refuted Simovic's claims in a brief filed by law firm Baker & McKenzie. It said Simovic didn't comply with online procedures, and cited withdrawal limits that would have required two months for him to draw down his account. That rebuttal was submitted to the court three weeks before Mt. Gox filed for bankruptcy protection on Feb. 28, saying it had lost bitcoins and cash worth more than half a billion dollars to hackers. The lawsuit was cited in a U.S. bankruptcy filing earlier this week, which is related to the company's Tokyo bankruptcy proceedings. Read more.