Along with the media, men toting Kalashnikovs showed up.

“Russia is always interesting,” Mr. Maksimov says. He was whisked out of the hotel in a Russian version of a “perp walk.” Soon enough, he was handcuffed to a chair in a dingy police station on the city’s outskirts.

FORMALLY, he was held on charges related to the payment to his girlfriend, which had in any case been repaid to the Maxi Group. But Mr. Maksimov says the investigator also discussed with him the arbitration with Novolipetsk. As Mr. Maksimov recalls it, the investigator sat on the edge of the table during the questioning and asked: “’You were offered $100 million. Why didn’t you take it?”

Mr. Maksimov says he was then escorted to the airport to fly to a prison in Yekaterinburg, in the Urals. Awaiting the flight, he says, he was again urged to make a deal with Novolipetsk.

“You won’t like people in jail,” he says he was told. “They aren’t your type.”

Anton Bazulev, director of external relations for Novolipetsk, said in an interview that it had never made a settlement offer to Mr. Maksimov and denied that it had orchestrated his arrest. Mr. Bazulev said Novolipetsk handed evidence to the police of possible fraud and was obliged to do so under Russian law as a publicly traded company.

Five days after his arrest, Mr. Maksimov was released on bail. A month later, in March, a Moscow International Commercial Arbitration panel awarded him $287 million in a ruling that, under terms of the chamber, is final and not subject to appeal.

When capitalism and democracy arrived in Russia in the early 1990s, many people thought a new industrialist class would become a pillar of the state, substituting for the Communist Party, the Red Army and the K.G.B. But under Mr. Putin, a K.G.B. veteran, the security services resurged as a force in society and business. Last Sunday’s poor election showing for his party, United Russia, suggests some Russian voters are cooling toward Mr. Putin, who intends to wage his own three-month campaign to return to the presidency.

In 2000, when he first ran for president, he vowed to eliminate the oligarchs “as a class,” but that didn’t happen. Some who seemed to clash with him directly, like Mr. Khodorkovsky, lost fortunes.