The U.S. Securities and Exchange Commission says it has filed criminal charges against 6 former officers of Putnam Fiduciary Trust Company.

SEC officials say the problems involved began when Putnam Fiduciary, Boston, a unit of Putnam Investments, made a 1-day delay in investing about $4 million of a client’s retirement plan assets.

Rather than telling the employer client about the error, the defendants “engaged in a fraudulent scheme to conceal and cover up” the error, SEC lawyers allege in a complaint filed in the U.S. District Court in Boston.

The defendants “schemed” to shift about $2.7 million of the losses to Putnam mutual fund shareholders by making “after-the-fact changes to the dates and the prices at which the plan had purchased and sold mutual fund shares,” and they let the retirement plan client bear the rest of the loss, the SEC lawyers allege.

The SEC says it is not charging Putnam Fiduciary or Putnam Investments, which is a unit of Marsh and McLennan Companies Inc., New York, because Putnam Fiduciary reported the problems itself and provided “swift, extensive and extraordinary cooperation.”

The defendants named by the SEC are Karnig Durgarian Jr., former chief of operations for Putnam Fiduciary; Donald McCracken, the company’s former head of global operations services; Virginia Papa, the company’s former director of defined contribution servicing; Sandra Childs, a former managing director who ran Putnam Fiduciary’s compliance department; Kevin Crain, a former managing director who ran Putnam Fiduciary’s plan administration unit; and Ronald Hogan, a former vice president who was in charge of new business implementation at Putnam Fiduciary.

Five of the defendants could not immediately be reached for comment.

Frank Libby Jr., an attorney for Durgarian put out a statement asserting that Durgarian’s years in the investment industry have earned Durgarian an “impeccable reputation for integrity and the respect of his colleagues.”

“He looks forward to his opportunity to contest the SEC’s claims here, and if it gets that far, to have all of the facts brought before an impartial judge and jury,” Libby says.

Putnam Investments President Charles Haldeman Jr. issued a statement emphasizing that Putnam reported its concerns about the fiduciary trust operations itself.

“The SEC has decided to take no action against Putnam in connection with the former employees’ unacceptable conduct because of our swift, extensive, and extraordinary cooperation,” Haldeman says in the statement. “We believe the decisive actions that our new management team took after discovering this issue demonstrate how seriously we take such matters.”

Putnam reported the “issue” to clients, regulators, auditors, fund trustees, and the press when it learned about the issue in 2004, made full restitution of about $4 million to the affected client and affected Putnam funds, and “took appropriate action against those individuals involved, including terminations,” Haldeman says.

Putnam also hired an outside firm to look for evidence of similar problems and improved its policies and procedures to prevent similar situations from happening again, Haldeman says.

“We have worked hard at Putnam to create a culture in which all of our colleagues value the importance of taking care of other people’s money and putting our clients first,” Haldeman says. “We believe that the steps we took after discovering this issue are proof of the strength of that culture, and we are firmly committed to these fiduciary principles.”