The Justice Department conducted criminal investigations into whether Mr. Bissonnette had disclosed classified information in his book or speeches and whether he had violated conflict-of-interest laws in consulting for companies that had contracts with SEAL Team 6. In the end, the department did not bring any criminal charges, settling instead for the cash forfeitures.

Mr. Bissonnette said in a statement Friday that he regretted his failure to submit “No Easy Day” for vetting before it was published in 2012 so Pentagon officials could ensure that it did not include classified information. Mr. Bissonnette acknowledged that he was required under his security clearances to let the Pentagon review the book, and he blamed another lawyer for advising him that he did not need to do so.

“I acknowledge my mistake and have paid a stiff price, both personally and financially, for that error,” he said. “I accept responsibility for failing to submit the book for review and apologize sincerely for my oversight.”

Documents filed in Federal District Court in Alexandria on Friday indicated that Mr. Bissonnette must transfer nearly $6.8 million to the government as part of the settlement. The amount includes all of the $6.7 million in royalties he has earned on “No Easy Day,” as well as $100,000 in fees for six speeches he gave in early 2013 before the government approved the slides he used in such presentations.

Mr. Bissonnette wrote in “No Easy Day” that he was one of the SEALs who shot Bin Laden, and he and Robert O’Neill, another former SEAL Team 6 member who claims his shots were the fatal ones, have competed on the lecture circuit. Military officials said that Mr. O’Neill is writing a book of his own and has asked the Pentagon to vet it.