diff --git a/data/spot.py b/data/spot.py
index 277a671..32f2221 100644
--- a/data/spot.py
+++ b/data/spot.py
@@ -243,9 +243,9 @@ class Spot:
         # should catch e.g. POTA comments like "2-fer: GB-0001 GB-0002".
         if self.comment and self.sig_refs and len(self.sig_refs) > 0:
             sig = self.sig_refs[0].sig.upper()
-            all_comment_refs = re.findall(get_ref_regex_for_sig(sig), self.comment)
-            for ref in all_comment_refs:
-                self.append_sig_ref_if_missing(SIGRef(id=ref.upper(), sig=sig))
+            all_comment_ref_matches = re.finditer(r"(^|\W)" + get_ref_regex_for_sig(sig) + r"(^|\W)", self.comment)
+            for ref_match in all_comment_ref_matches:
+                self.append_sig_ref_if_missing(SIGRef(id=ref_match.group(2).upper(), sig=sig))
 
         # See if the comment looks like it contains any SIGs (and optionally SIG references) that we can
         # add to the spot. This should catch cluster spot comments like "POTA GB-0001 WWFF GFF-0001" and e.g. POTA