A US district judge has rejected a claim by Mizuho Bank that a class action lawsuit related to its relationship with failed bitcoin exchange Mt Gox should be moved to Japan.

Once the largest global bitcoin exchange, Tokyo-based Mt Gox collapsed in 2014, eventually filing for bankruptcy. Since then, the exchange, and its founder and CEO Mark Karpeles, have been embroiled in a lawsuits from customers seeking to recover millions in customer funds that remain unaccounted for.

Mizuho was first named as a defendant in a class action lawsuit brought by former exchange users in March 2014 as it served as Mt Gox’s banking partner, receiving fiat funds deposited by customers into the exchange and held by Mt Gox.

In the latest ruling, U.S. District Judge Gary Feinerman criticized actions taken by the bank, suggesting it profited from its affiliation with Mt Gox even as it sought to limit the number and amount of customer withdrawals over concerns regarding its liability for deficiencies in the exchange’s business model.

Feinerman wrote:

The ruling goes so far as to allege that Mizuho prevented Mt Gox from telling customers that the bank was the cause of withdrawal issues, or that it was seeking to terminate its relationship with the now-defunct bitcoin exchange.

“Mizuho knew that if Mt Gox’s members learned of its prohibition on withdrawals of fiat currency from Mt Gox’s Mizuho account, members would stop making deposits and Mizuho would stop collecting the associated fees,” Feinerman wrote.

The class action lawsuit alleges that Mizuho "tortiously interfered" with the plaintiffs agreements with Mt Gox by affecting its ability to conduct business, and that it unjustly enriched itself through these actions.

In statements, representatives from Edelson PC lauded the decision, stating:

While Feinerman denied Mizuho’s request, he did find that the class action lawsuit would need to produce a new plaintiff, or otherwise be required to move to the Central District of California.

At issue is that the lawsuit was brought by Illinois resident Gregory Greene, an individual who never sent fiat funds to the exchange, and as a result, never had "transactional contacts" with Mizuho.

"Plaintiffs have not established that Mizuho Bank had sufficient suit-related contacts with Illinois to meet the standard articulated in Walden v Fiore, or that their claims arose out of Mizuho Bank’s contracts with Illinois," the judge wrote.

As a result, Feinerman stated that the case should be moved to California, as plaintiff Joseph Lack transferred funds from his local bank to Mizuho.

"Mizuho knowingly accepted a deposit from a bank it knew to be in California and from somebody it knew to be a California resident, knowing that it would not allow that money to be withdrawn, despite having concealed the no-withdrawal policy for the purpose of enticing such deposits," he wrote.

However, prior to transferring the case, the judge is allowing the lawsuit to add an additional plaintiff who might better represent the lawsuit and its grounds for location in Illinois.

Feinerman concluded:

Memorandum Opinion and Order

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