diff --git a/Trigger/TriggerCommon/TriggerMenu/python/jet/smc_string_conversions.py b/Trigger/TriggerCommon/TriggerMenu/python/jet/smc_string_conversions.py
index 7a7ee1ce4290bf36e1303dfad630c01f6415e585..1536b26241f8ffa920920201af306025aa950ee0 100644
--- a/Trigger/TriggerCommon/TriggerMenu/python/jet/smc_string_conversions.py
+++ b/Trigger/TriggerCommon/TriggerMenu/python/jet/smc_string_conversions.py
@@ -3,9 +3,8 @@
 """convert standard string such as nosmc, 0smc30, -INFsmc30,
 30smcINF, to smc_min, smc_max strings"""
 
-
 import re
-smc_range_re = re.compile(r'(?P<smc_min>((-)?\d|-?INF))smc(?P<smc_max>((-)?\d|-?INF))')
+smc_range_re = re.compile(r'^(?P<smc_min>((-)?\d+|-?INF))smc(?P<smc_max>((-)?\d+|-?INF))$')
 
 def _extract(smc_range):