diff --git a/.hooks/pre-commit.d/check_portepoch b/.hooks/pre-commit.d/check_portepoch
index 34d93e2efcf4..1a59a39b5407 100755
--- a/.hooks/pre-commit.d/check_portepoch
+++ b/.hooks/pre-commit.d/check_portepoch
@@ -1,27 +1,27 @@
 #!/bin/sh
 #
 # Check that PORTEPOCH is not being dropped, and is non-decreasing
 #
 
 check_epoch() {
 	local makefile="$1"
-	local old_epoch=$(git diff --cached -U0 "${makefile}" | grep '^-PORTEPOCH.*=' | grep -oE '[0-9]+')
-	local new_epoch=$(git diff --cached -U0 "${makefile}" | grep '^+PORTEPOCH.*=' | grep -oE '[0-9]+')
-	if [ -z "${new_epoch}" -a -n "${old_epoch}" ] ; then
+	local old_epoch=$(git diff --cached -U0 "${makefile}" | grep '^\-PORTEPOCH' | grep -oE '[0-9]+')
+	local new_epoch=$(git diff --cached -U0 "${makefile}" | grep '^\+PORTEPOCH' | grep -oE '[0-9]+')
+	if [ -z "${new_epoch}" ] ; then
 		echo "[pre-commit] dropped PORTEPOCH ${old_epoch} in ${makefile}"
 		exit 1
 	fi
 	if [ -n "${old_epoch}" ] ; then
 		if [ ${new_epoch} -lt ${old_epoch} ] ; then
 			echo "[pre-commit] PORTEPOCH decreasing from ${old_epoch} to ${new_epoch} in ${makefile}"
 			exit 2
 		fi
 	fi
 }
 
 modified_makefiles=$(git diff --name-only --cached --diff-filter=M -GPORTEPOCH | grep -E '^[^/]+/[^/]+/Makefile$')
 if [ $? -eq 0 ] ; then
 	for modified_makefile in ${modified_makefiles} ; do
 		check_epoch ${modified_makefile}
 	done
 fi