The S.E.C. said it sought out other bids over the last year and even considered building its own database, an effort that would have taken several years and cost millions of dollars more than the Tradeworx project. Mr. Berman added that the agency looked to Tradeworx only for data feeds that were the same no matter who provided them.

The chief executive of Tradeworx, Manoj Narang, argued that if he sold bogus data to the government, it would be obvious. More important, he said, the S.E.C. has few alternatives.

“Where else are they going to be able to get these capabilities?” Mr. Narang said. “They are not available from anywhere other than high-speed trading firms. We’re the only ones who possess it.”

Today, the S.E.C. relies on the official trading record, known as the consolidated tape, which includes the price of every trade executed on any of the nation’s stock exchanges. Most sophisticated trading firms bypass the official record by buying data directly from the exchanges. The firms compile a full record milliseconds before the consolidated tape is assembled and obtain a wider range of information, including orders that are submitted but never executed.

Mr. Berman said that data from Tradeworx would be used throughout the S.E.C., from the enforcement division looking to catch wrongdoing to the division of trading and markets that keeps daily watch over the markets. The data could allow the S.E.C. to analyze claims that some firms take advantage of their faster data feeds to jump in front of slower traders, and complaints that sophisticated traders can jam the system with so many orders that it slows down trading for others.

Mr. Berman, a former hedge fund co-manager and nuclear physicist, led the agency’s examination of the flash crash of 2010, when the Dow Jones industrial average plunged 5 percent in five minutes and then mostly recovered. He is now leading the broader effort to bring the S.E.C. into the modern world of trading. As the agency falls further behind, he is helping to build a new Office of Research and Analytics, which is looking to hire people with experience on Wall Street and in computer programming. The agency is also moving closer to creating a so-called consolidated audit trail, which will allow regulators to see the identity of the firm behind every trade.

But any future efforts depend on the S.E.C. having access to the sort of basic data that Tradeworx will provide.