diff --git a/jjb/shell/tagcollisionreject.sh b/jjb/shell/tagcollisionreject.sh
index 86fe317..09c014c 100755
--- a/jjb/shell/tagcollisionreject.sh
+++ b/jjb/shell/tagcollisionreject.sh
@@ -22,6 +22,8 @@
 VERSIONFILE="" # file path to file containing version number
 NEW_VERSION="" # version number found in $VERSIONFILE
 
+SEMVER_STRICT=${SEMVER_STRICT:-0} # require semver versions
+
 releaseversion=0
 fail_validation=0
 
@@ -64,7 +66,13 @@
     echo "Version string '$NEW_VERSION' found in '$VERSIONFILE' is a SemVer released version!"
     releaseversion=1
   else
-    echo "Version string '$NEW_VERSION' found in '$VERSIONFILE' is not a SemVer released version, skipping."
+    if [ "$SEMVER_STRICT" -eq "1" ]
+    then
+      echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is not a SemVer released version, SEMVER_STRICT enabled, failing!"
+      fail_validation=1
+    else
+      echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is not a SemVer released version, skipping."
+    fi
   fi
 }
 
diff --git a/jjb/shell/versiontag.sh b/jjb/shell/versiontag.sh
index 4287914..60042d8 100755
--- a/jjb/shell/versiontag.sh
+++ b/jjb/shell/versiontag.sh
@@ -23,6 +23,8 @@
 VERSIONFILE="" # file path to file containing version number
 NEW_VERSION="" # version number found in $VERSIONFILE
 
+SEMVER_STRICT=${SEMVER_STRICT:-0} # require semver versions
+
 releaseversion=0
 fail_validation=0
 
@@ -53,7 +55,13 @@
     echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is a SemVer released version!"
     releaseversion=1
   else
-    echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is not a SemVer released version, skipping."
+    if [ "$SEMVER_STRICT" -eq "1" ]
+    then
+      echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is not a SemVer released version, SEMVER_STRICT enabled, failing!"
+      fail_validation=1
+    else
+      echo "Version string '$NEW_VERSION' in '$VERSIONFILE' is not a SemVer released version, skipping."
+    fi
   fi
 }