diff --git a/tcl/Sdc.tcl b/tcl/Sdc.tcl
index 9566572f..8f2e42c0 100644
--- a/tcl/Sdc.tcl
+++ b/tcl/Sdc.tcl
@@ -1004,7 +1004,7 @@ proc get_ports { args } {
   return $ports
 }
 
-variable filter_regexp1 {@?([a-zA-Z_]+) +(==|=~) +([0-9a-zA-Z_\*]+)}
+variable filter_regexp1 {@?([a-zA-Z_]+) *(==|=~) *([0-9a-zA-Z_\*]+)}
 variable filter_or_regexp "($filter_regexp1) +\\|\\| +($filter_regexp1)"
 variable filter_and_regexp "($filter_regexp1) +&& +($filter_regexp1)"