A federal court in New York ordered Iat Hong, Bo Zheng and Hung Chin to pay fines, as well as Hong's mother Sou Cheng Lai who held a bank account where the proceeds from the stock sales were kept, according to a copy of the judgment posted by SC Media.

Accessed emails

The three hackers installed malware on the law firms' computer networks, which empowered them to access emails on mergers and acquisitions in which the firms were involved. With the information, the attackers purchased stock in at least three public companies prior to their merger announcements, according to the Securities and Exchange Commission (SEC), which filed the lawsuit against the hackers.

In advance of mergers

Accoring to the SEC the hackers shelled out roughly $7.5 million within a month's time to buy shares in Altera in advance of its 2015 acquisition by Intel, snapped up shares in Borderfree before its 2015 buyout by Pitney Bowes, and also acquired shares in InterMune before its 2014 merger deal with Roche, racking in close to $3 million in illegal profits.