This year, SEPTA contracted with Vandor Strategies L.L.C., also a Washington lobbyist.
In a two-page letter dated Thursday, Federal Transit Administration chief counsel Dorval Carter said SEPTA failed to disclose lobbying "on at least five separate occasions."
In some years, Carter said, "SEPTA may have had to supplement its lobbying disclosure forms quarterly" and thus "the total number of failures may be far higher."
Carter said in his letter, sent to SEPTA general manager Joseph M. Casey, that he wanted additional information by July 20 to determine "the appropriate penalty."
Fines for not disclosing lobbying, he said, are between $10,000 and $100,000 for each failure.
SEPTA spokesman Jerri Williams said only that her agency was reviewing Carter's letter and would respond promptly.
"We're reviewing it, and we'll prepare our response by the July 20 deadline," she said.
The federal action came after The Inquirer questioned SEPTA about its payments to the politically connected lobbyists.
The last time the Federal Transit Administration issued a major fine was against Chicago's Metra regional rail agency in May 2011.
All of SEPTA's lobbying firms have been major contributors to Pennsylvania political candidates.
Additionally, some of the firms employ well-known Philadelphia political figures. Former City Controller Jonathan Saidel, for example, is listed as a "special consultant" on SEPTA's contract with Duane Morris.
Melonese Shaw, a former contractor with the Philadelphia School District and a longtime associate of State Rep. Dwight Evans (D., Phila.), is another consultant listed on the Duane Morris contract.
In the firm's contract proposal, Shaw said she would serve a lobbyist and "utilize the many contacts I have in Pennsylvania and Washington."
Saidel, in an e-mail to The Inquirer, said he had not worked on the SEPTA project though he had worked for Duane Morris. Shaw did not respond to requests for comment.
Before the federal action, SEPTA chief financial officer Richard Burnfield and Francis Kelly, SEPTA's assistant general manager of public and government affairs, insisted in an interview with an Inquirer reporter that their agency did not have to tell federal officials about its payments to lobbying firms.
They contended that the Washington firms were being paid only for consulting work, none of which was lobbying.
SEPTA took a similar position in a May 22 letter to the Federal Transit Administration.
The letter said SEPTA had decided "to take a conservative approach and file at this time."
The letter further said: "SEPTA legislative consultants do not engage in lobbying efforts to obtain federal grants from the Federal Transit Administration."
But SEPTA's contracts with the lobbying firms gave a clear idea of the work they were doing for the transit agency.
Howard Marlowe, president of the American League of Lobbyists, reviewed one SEPTA contract for The Inquirer and said it listed "typical lobbying responsibilities."
Stephen Spaulding, an attorney with Common Cause, said the contract information shows that "they're being paid essentially for access on Capitol Hill."
Melanie Sloan, executive director of Citizens for Responsibility and Ethics in Washington, said: "It's a lobbying contract. End of story."
The transit administration also reviewed SEPTA's contracts with lobbyists and the invoices the firms submitted before deciding that SEPTA had violated federal law.
By the July 20 deadline, SEPTA must detail the amount paid to lobbyists, the people who performed the lobbying work, the subcontractors of the lobbyists, and the federal actions that lobbyists were trying to influence.
The federal agency's investigation of SEPTA has set off a nationwide review of filings by transit agencies. On Friday, it sent e-mails to more than 1,000 local agencies, stating that disclosure reports must be filed if they paid more than $25,000 to a lobbyist to influence the federal government.
Contact Mark Fazlollah at 215-854-5831 or mfazlollah@phillynews.com.