RCS was designed and built by Walter F. Tichy of Purdue University.
RCS version 3 was released in 1983.

Adam Hammer, Thomas Narten, and Daniel Trinkle of Purdue supported RCS
through version 4.3, released in 1990.  Guy Harris of Sun contributed
many porting fixes.  Paul Eggert of System Development Corporation
contributed bug fixes and tuneups.  Jay Lepreau contributed 4.3BSD
support.

Paul Eggert of Twin Sun wrote the changes for RCS versions 5.5 and 5.6
(1991).  Rich Braun of Kronos and Andy Glew of Intel contributed ideas
for new options.  Bill Hahn of Stratus contributed ideas for setuid
support.  Ideas for piece tables came from Joe Berkovitz of Stratus and
Walter F. Tichy.  Matt Cross of Stratus contributed test case ideas.
Adam Hammer of Purdue QAed.

Paul Eggert wrote most of the changes for RCS 5.7.  K. Richard Pixley
of Cygnus Support contributed several bug fixes.  Robert Lupton of
Princeton and Daniel Trinkle contributed ideas for $Name expansion.
Brendan Kehoe of Cygnus Support suggested rlog's -N option.  Paul
D. Smith of Data General suggested improvements in option and error
processing.  Adam Hammer of Purdue QAed.

Thien-Thi Nguyen wrote the changes for RCS 5.8 and onwards.
A big thanks go to the following people for suggesting features
and reporting bugs (sometimes with fixes) for these releases:
  Aaron W. Swenson
  Ian Delaney
  Karl Berry
  Keith Thompson
  Klaus T. Aehlig
  Ludovic Courtès
  Michael Sanders
  Mike Dooley
  Mike Mestnik
  Nelson H. F. Beebe
  Oliver Billmann
  Paul Ackersviller
  Paul Eggert
  Ralf Wildenhues
  Rob Vermaas
  Romain Francoise
  Martin Burnicki
  Bostjan Vilfan
  Honza Horak
  Carlie J. Coats, Jr.
  Jiri Moskovcak
  James Olin Oden
  Derek McEachern
  Andrew J. Schorr
  (and others who prefer anonymity)