When Mt. Gox, the world's largest bitcoin trading exchange, collapsed in early 2014, more than 24,000 customers around the world lost access to hundreds of millions of dollars' worth of cryptocurrency and cash.

More than three years later, with the price of bitcoin skyrocketing to more than $10,000 in some markets, not a single customer has recouped a single cent, crypto or otherwise. It's not clear when they will. The failed exchange has become stuck in a morass of litigation — a Russian doll of bankruptcies in Japan and New Zealand, four in all, plus lawsuits in the United States and competing claims from creditors.

And although the Mt. Gox bankruptcy trustee recovered digital currency now worth more than $1.6 billion, under Japanese law the exchange's customers likely will recover only a fraction of that.