But he gained notoriety in 2008 when derivatives bets his group had made on subprime mortgages went south, resulting in calls for collateral from A.I.G.'s customers that the company could not meet.
Lawyers for Lehman's creditors wrote in a court filing that they and the estate served Mr. Geithner with a subpoena last August, ordering him to testify about conversations he had held with both JPMorgan and Lehman over the former's calls for collateral in early September 2008.
Goldman was right to question the prices, make calls for collateral, and protect itself.
Mr Lin does call for easier collateral and credit registries.
"All we did is call for the collateral that was due to us under the contracts," he said.
Paramax was concerned, the court filing said, that UBS could mark to market downward the value of the notes, causing a call for more collateral beyond the initial $4.6 million.
"All we did was call for the collateral that was due to us under the contracts," Viniar said.
Mr. Zouvelos acknowledged that Ms. George's contract called for the collateral to be returned in 90 days, and he said he was not sure why she had not received it within that period.
Just a week ago, Carlyle Capital warned the market that it had begun to receive default notices after getting margin calls for additional collateral from lender banks.
Even as the government was racing to save AIG from a market-jolting collapse last September, Goldman did not see the need to stop calling for more collateral from the liquidity-squeezed insurer, nor did it get particularly involved in the government rescue efforts.
