The Philadelphia public-TV station WHYY is one of four nonprofit groups that will cooperate with NBC TV stations, now part of the Comcast Corp., as part of an experiment to boost local news coverage.

Comcast pledged to seek partnerships with nonprofits during discussions with federal regulators over its purchase of NBC Universal Inc., a deal that closed in early 2011. The voluntary agreement addressed concerns over weakened local news coverage because of media consolidation.

The other nonprofit groups are ProPublica in New York, the Chicago Reporter, and the Los Angeles public-radio station KPCC. NBC Universal will continue an existing agreement with a fifth group, the

NBC Universal, which owns 10 local TV stations in major markets, says it will donate funds to the nonprofit organizations. A spokeswoman did not say how much. ProPublica and WHYY officials also declined to disclose the amounts.

ProPublica general manager Richard Tofel said the investigative journalism group would itemize the amount in its 990 nonprofit tax filing with the IRS. "We hope there will be future donations," he said, noting it was a three-year agreement.

Local NBC TV stations would be given advance previews of national data projects by ProPublica that could be mined and localized by the stations, Tofel said.

"We think this is a terrific opportunity to get broader distribution for our significant content," he said. ProPublica has won two Pulitzer Prizes, one for the financial crisis and the second on euthanasia at a New Orleans hospital immobilized by Hurricane Katrina, published in partnership with the New York Times Sunday magazine.

Bill Marrazzo, president and chief executive officer at WHYY, which serves eastern Pennsylvania, South Jersey, and Delaware, said that the agreement was "pretty open-ended" and that "the day-to-day business processes have not been worked out."

He believed WHYY brought several strengths to the partnership, which include its newsgathering in Delaware, deeper story content, and the site. The donation accompanying the agreement was "appreciated but not material," Marrazzo said.

Chris Blackman, vice president of news for NBC 10, said: "The next step for us is to get together with WHYY and brainstorm. I think we both bring something to the table. . . . The first thing is taking baby steps and working out the logistics. But it's thrilling."