In examining the $4 billion mixed-use Atlantic Yards project for approval, New York State’s leading development agency never saw a business plan from developer Forest City Ratner, documents and officials now say. The project, which plans more than 6,000 units of housing and a home for the Nets basketball team, was approved by the state just before Governor Pataki left office.

Critics contend that state officials should have reviewed a full financial model before promising hundreds of millions of dollars in public incentives and subsidies. Forest City’s full financial plan has long been sought by critics of the project and legislators, including Assemblyman James Brennan of Brooklyn, who sued the Empire State Development Corporation to obtain it last month, presuming that it was in their possession. The Empire State Development Corporation has denied Mr. Brennan’s repeated records requests for the comprehensive model.

A spokesman for the Empire State Development Corporation, Errol Cockfield, now says the state has never seen or possessed any comprehensive business plan from the developer. He said the state has relied on a report written by a consulting group, KPMG, to judge the amount of revenue the developer would stand to make from the project.

“We brought in KPMG to take a look at all the forces involved,” Mr. Cockfield said. “We feel very confident that that data allowed them to take a thorough look at the project in its long-term value for taxpayers.”

In the KPMG report, the consultant says it was not provided with a comprehensive financial model by Forest City Ratner. Cash flow projections and interviews with executives were the basis for the report’s conclusion that the developer would stand to make a total return on its investment of about 9.8% on the mixed-use portion of the project.

A former city planning commissioner who opposes the project, Ronald Shiffman, said that in not seeing FCR’s financial plan, the state did not provide appropriate oversight.

“One would believe they should look at it with a lot of due diligence, particularly with the amount of money they’re putting into this,” he said. “It’s been a done deal from the beginning without anybody really looking at it.”

A spokesman for Forest City Ratner declined to comment.

Since taking over from the Pataki administration in January, the leadership of Governor Spitzer’s Empire State Development Corporation, which is involved in numerous large-scale developments including Moynihan Station and the Javits Center, has pledged to be a tougher negotiator with private developers.

“We’re going to be as aggressive as possible in making sure that the public gets an impressive rate of return,” Mr. Cockfield said. “That philosophy is central to everything we do.”