diff --git a/SabreTools.Core/Filter/FilterObject.cs b/SabreTools.Core/Filter/FilterObject.cs
index a70ed76b..dce42bed 100644
--- a/SabreTools.Core/Filter/FilterObject.cs
+++ b/SabreTools.Core/Filter/FilterObject.cs
@@ -378,7 +378,7 @@ namespace SabreTools.Core.Filter
             operation = GetOperation(match.Groups["operation"].Value);
 
             // Only non-zero length values are counted as non-null
-            if (value?.Length > 0)
+            if (match.Groups["value"]?.Value?.Length > 0)
                 value = match.Groups["value"].Value;
 
             return true;