The following people have been contributed into FreeArc:

Igor Pavlov, author of 7-zip, LZMA and EXE filter: licensed under the GNU LGPL license and available for free at http://www.7-zip.org
Dmitry Shkarin, author of PPMd: distributed to public domain and available for free at http://www.compression.ru/ds/
Ilya Grebnov, author of GRZipII and original LZP filter: licensed under the GNU LGPL license
Alexander Djourik and Pavel Zhilin, authors of TTA: licensed under the GNU GPL license and available for free at http://true-audio.com/
Tom St Denis, author of LibTomCrypt: distributed to public domain and available for free at http://libtomcrypt.com/
Dmitry Subbotin, author of Carryless rangecoder: distributed to public domain and available for free at http://www.compression.ru/ds/
Joachim Henke, coauthor of Tornado: licensed under the GNU GPL license and available for free at http://freearc.org/Research.aspx
Mark Shevchenko (author of GUI SFX and web site)
Bulat Ziganshin (author of remaining parts)