The San Francisco 49ers were fined $500,000 yesterday by NFL Commissioner Paul Tagliabue for violating the league's corporate ownership policy but were spared stronger penalties that could have cost them draft choices.

Tagliabue, who sent a letter of notification to 49ers owner Edward DeBartolo Jr. in his Youngstown, Ohio, office, ruled that the violations happened when DeBartolo made the team a subsidiary of the DeBartolo Corp., a corporation having substantial non-football business operations, in December 1986 without notifying other owners or getting permission from the league.

The move made the 49ers part of the same corporation, headed by DeBartolo's father, that owns the Pittsburgh Penguins of the National Hockey League, a violation of a league rule that an NFL team cannot have an interest in another professional sport.

But, perhaps most important to the football team, Tagliabue said he didn't believe the 49ers bought their four Super Bowls through a competitive advantage gained by the ownership setup. He postponed a decision on whether the 49ers would have to revert to their previous ownership structure, pending an NFL review.

"I find that the 49ers' transfer has not to date resulted in any identifiable competitive advantage that would warrant such a sanction," Tagliabue said in his letter to DeBartolo. "In particular, I find that the 49ers' extraordinary playing-field success during the 1980s -- both before and after the December 1986 ownership transfer -- was achieved on the merits and not by reason of any violation of the league constitution or other policies."

Last spring, Tagliabue hinted at this, saying that since the 49ers won two Super Bowls before the ownership arrangement was changed, there had to be more to their success than the DeBartolo checkbook. Several rival NFL owners had charged that DeBartolo had bought his Super Bowl victories by offering large contracts to free agents such as Matt Millen, Jim Burt and Fred Smerlas.

"We are pleased with the commissioner's conclusive findings that the San Francisco 49ers have not gained a competitive advantage through corporate ownership," the 49ers said in a statement. "We recognize the commissioner faced an extremely difficult decision and are convinced of his resolve in this matter. Certainly, we will adhere to and abide by his ruling."

The 49ers could have been fined $1 million for violating two NFL rules: improperly transferring the controlling interest of the club to a subsidiary of the DeBartolo Corp.; and transferring the 49ers to the corporation when it owned and operated the Penguins as a subsidiary company.

But Tagliabue chose to fine the team $250,000 for each violation.

Three other NFL teams have been reported to be in violation of the corporate ownership rule -- Washington, Houston and Minnesota -- but Tagliabue has not planned any action on those cases, according to a league spokesman.