Announced today in the NY Times:

W. Mark Felt, who was the No. 2 official at the F.B.I. when he helped bring down President Richard M. Nixon by resisting the Watergate cover-up and becoming Deep Throat, the most
famous anonymous source in American history, died Thursday. He was 95
and lived in Santa Rosa, Calif.

W. Mark Felt, left, with reporters in Washington in 1980. Mr. Felt and
Edward S. Miller, right, were fined $8,500 for approving illegal
break-ins.

His death was confirmed by Rob Jones, his grandson.

In 2005, Mr. Felt revealed that he was the one who had secretly supplied Bob Woodwares of The Washington Post with crucial leads in the Watergate affair in
the early 1970s. His decision to unmask himself, in an article in
Vanity Fair, ended a guessing game that had gone on for more than 30
years.