Thierman, a labor lawyer by trade, was the architect of class action overtime suits on behalf of brokers that kicked off in 2005. (Thierman has settled for tens of millions of dollars with every major wirehouse regarding the overtime issue, including a $98 million deal with then Citigroup Smith Barney.) He's taking on the Wall Street brokerages again, and if he has his way, contracts like Banus' will be void and brokers won't have to pay back those upfront payments when they leave a firm. At the very least, they won't have to pay them back immediately upon departure as the acceleration clauses require. What's more, advisors who have already paid back their loans could be awarded damages. At Citigroup, such damages could add up to $50 million or more, attorneys and compensation consultants estimate. If the suit against Citigroup goes well, Thierman says he may file similar suits against other wirehouse firms with similar contracts.