Dow Lohnes Government Strategies said it terminated its contract with Bernard L. Madoff Investment Securities, a client that spent more than $400,000 on lobbying in the past decade, the Politico reported Tuesday.
Authorities have accused Madoff of running a $50 billion Ponzi scheme, paying investors with other investors' money, rather than legitimate earnings.
Madoff's influence runs from political donations of more than $380,000 to political candidates since 1993 to a position on board of directors of the Securities Industry and Financial Markets Association, a financial services lobbying group.
"We're looking at everything based on the unfolding facts and taking this very seriously, as you can imagine," said SIFMA spokesman Travis Larson.
There is also a suspicious family tie-in.
Former Securities and Exchange Commission assistant director of Compliance and Examinations Eric Swanson is married to Madoff's niece, the Politico said.
Swanson left the SEC in 2006 and married Shana Madoff in 2007.
Lori Richards, director of compliance inspections and examinations, said Swanson helped review Madoff's firm in 1999 and 2004.