diff --git a/winsup/CONTRIBUTORS b/winsup/CONTRIBUTORS
index 61fba810b..0f50f3f5e 100644
--- a/winsup/CONTRIBUTORS
+++ b/winsup/CONTRIBUTORS
@@ -77,6 +77,7 @@ Joshua Daniel Franklin			joshuadfranklin@yahoo.com
 Ken Brown				kbrown@cornell.edu
 Lapo Luchini				lapo@lapo.it
 Lev Bishop				lev.bishop@gmail.com
+Mark Geisert				mark@maxrnd.com
 Max Kaehn				slothman@electric-cloud.com
 Micha Nelissen				mdvpost@hotmail.com
 Michael Haubenwallner			michael.haubenwallner@ssi-schaefer.com