The founders of a project and portfolio management system whose scheduling products have become standard tools for many industry firms announced on May 1 that they have taken in two venture capital partners, giving up approximately 75% of the company in the process.

Without revealing terms, Primavera Systems CEO Joel M. Koppelman and Chief Technology Officer Richard K. Faris announced on the Bala Cynwyd, Pa.-based firm’s 23rd anniversary that they have sold “substantial” interests to Francisco Partners and Insight Venture Partners. Francisco has locations in Menlo Park, Calif., and London, England. Insight is based in New York City.

The investors each have track records investing in technology, software and Internet companies, says Koppelman. He says he is counting on their business and deal-making acumen to help Primavera grow, especially through acquisitions and international development. “I give up a little bit of control and I have somebody who owns a big stake, but each will have a minority interest,” he says. “Together they will have a majority interest in the company—but it’s sort of a three-way play. As long as we can get either of these investors to agree with us, we get our way. It’s not all that different from dealing with Mom and Dad.”

He says he began looking into soliciting investment about a year ago, citing the company’s steady growth and favorable market conditions.

The deal will buy out Intel, a previous outside investor, Koppelman says. In an earlier round, Intel and i2 had together acquired 21.7% of Primavera, which still left Faris and Koppelman in control.

By contrast, Koppelman now expects more interaction. “I think with the kind of money we’re talking about that these guys will be much closer to the action,” he says. Koppelman also says the new partners “are very good in helping benchmark what we do in comparison with other companies,” but also have deep pockets and expertise for acquisitions.

“I don’t have a shopping list, but I think we have a pretty large vision for project resources and portfolio management, extending the product line, adding functionality and integrating from a single source, something customers want,” Koppelman says.