To Magna Excitement, Magna Carta Returns

The auction was held in late December. Rubenstein said yesterday that he learned about the auction the day before it was to happen. Fearing the document would be taken out of the country, he bought it for $21.3 million and vowed to return it to the archives. "The only place that's appropriate for that in the United States is the National Archives," he said.

"I come from a relatively modest background," Rubenstein said. He said his business success "made me really feel that I owed a lot to our country, and I wanted to repay it in a modest way."

He and Weinstein pulled the cover off the case, setting off a volley of camera clicks.

The heavy case is designed to moderate humidity and keep out as much oxygen as possible, said conservator Terry Boone. Oxygen causes deterioration, she said.

"It is in incredibly great condition, especially for its age," Boone said. "In the almost 25 years that we've had it here at the National Archives, we haven't seen any change at all."

The 15-inch-by-17-inch document is written in a vegetable-based ink on what is probably calf skin, Boone said. The ink is not absorbed, as happens with paper, but actually sits on the surface. "The ink doesn't bite in," she said, "so it's more likely to move."

Pinkert said the document's importance is simple. It acknowledges, he said, that "the king, too, has to obey the law."