Mary Jo White, the chair of the Securities and Exchange Commission, said Thursday she's concerned about a landmark federal appellate court decision that overturned two insider trading convictions.
"There's no a question it's a significant decision," White said in response to a question following a speech at the DealBook "Opportunities for Tomorrow" conference in New York.
"My initial sense," she said, is that it is an "overly narrow view of the insider trading law, and that is a concern."
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In a closely watched case, the 2nd U.S. Circuit Court of Appeals on Wednesday vacated the insider trading convictions of two former hedge fund managers stemming from trades in Dell and Nvidia.
The decision was a major setback for Manhattan U.S. Attorney Preet Bharara. Experts predicted the ruling could have a wide-ranging impact on the future of insider trading cases, and even affect SEC enforcement.
The SEC has focused heavily on cracking down on insider trading and regulating high frequency trading.
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In her keynote address at the conference, White laid out three aims of the commission concerning "modern" oversight of asset management.
These were: expanding data collection requirements, extending investing risk controls and ensuring that firms have a plan for transitioning assets when necessary.
"One of the postcrisis challenges," she said, "has been an emphasis on addressing risks that could have a systemic risk on securities markets or ... systems as a whole."
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We are "anticipating and planning for the worst," she said.
CNBC's Everett Rosenfeld contributed to this report.