Jim Bell reportedly was forced to resign as part of a push by activist investor Ryan Cohen to "reshape the ailing retailer.”
Commission suspends trading in an over-the-counter stock, SpectraScience, that is being "pumped" on social media sites.
Companies should address “the effects of a potential ‘short squeeze’ due to a sudden increase in demand for your stock.”
The stock trading app company also accessed $500 million through existing credit lines.
“There’s definitely some excessiveness out there right now, which has some professionals scratching their heads.”
The video game retailer reported no major news on Wednesday, suggesting the massive rally in the stock was simply a short squeeze.
The video game retailer will save about $157 million a year by eliminating the dividend as it struggles with shrinking profits.
The retailer believes it can still "leverage our industry-leading position to drive growth in the second half" of the year.
Strong demand for Nintendo Switch, PS4 Pro, and Xbox One X consoles powered the retailer's 12.2% gain in same-store sales.
The company believes its shift toward non-gaming businesses is paying off and sees "an abundance of business opportunities."
Shareholder Standard General has the lead bid, and a bankruptcy court has approved its use of "credit-bidding" to buy some of RadioShack's stores.