Average profit per equity partner (PEP) fell 4 per cent at Sullivan & Cromwell last year as the Wall St titan battled the impact of the economic downturn.
Despite the reduction, PEP at Sullivan remained at around the $3m mark, leaving it still the most profitable full-service US law firm.
The firm's 4 per cent drop is in contrast with several of its competitors which have seen more notable declines in profit last year.
Gross revenue at Sullivan showed no growth last year, remaining flat at $1.1bn.
A Sullivan insider said the firm’s focus on keeping a tight control over expenses had helped maintain profitability, as had a string of credit crunch-related mandates.
“We were quite busy,” the source said.
Last year, Sullivan played a role in almost all of the most significant deals on Wall St including acting for Bear Stearns’ board of directors on its takeover by JPMorgan Chase; mortgage giant Fannie Mae on its nationalisation; and AIG on its $85bn (£46bn) bailout by the Federal Reserve.
So far, however, 2009 was looking significantly less strong. When asked how the markets were looking so far this year the Sullivan source admitted, “very weak”.