The Financial Industry Regulatory Authority asked high-frequency trading firms to disclose details of their strategies and highly guarded computer code. Tom Gira, executive vice president of the market regulation unit at FINRA, said the requests are part of an investigation of suspicious market activities. "It's not a fishing expedition or educational exercise. It's because there's something that's troubling us in the marketplace," Gira said. The Securities and Exchange Commission also is asking about proprietary algorithmic trading data.