Here's an example of how not classified their existence is. This is a list of the commanding officers of SEAL Team Six readily available online.
Commander Richard Marcinko – Nov 1980 to July 1983
Captain Robert A. Gormly – 1983 to 1986
Captain Thomas E. Murphy – 1986 to 1987
Captain Richard T.P. Woolard – 1987 to 1990
Captain Ronald E. Yeaw – 1990 to 1992
Captain Thomas G. Moser – 1992 to 1994
Admiral Eric T. Olson – 1994 to 1997
Vice Admiral Albert M. Calland III – June 1997 to June 1999
Vice Admiral Joseph D. Kernan – 1999 to 2002
Rear Admiral Edward G. Winters, III – 2002 to 2004
Captain Eric Prescott
Rear Admiral Brian L. Losey
Rear Admiral Scott P. Moore
