diff --git a/pyvo/registry/rtcons.py b/pyvo/registry/rtcons.py
index 3f04e090e..906c55927 100644
--- a/pyvo/registry/rtcons.py
+++ b/pyvo/registry/rtcons.py
@@ -244,7 +244,7 @@ def _get_union_condition(self, service):
             "SELECT ivoid FROM rr.resource WHERE"
             " 1=ivo_hasword(res_title, {{{parname}}})",
             "SELECT ivoid FROM rr.res_subject WHERE"
-            " res_subject ILIKE {{{parpatname}}}"]
+            " rr.res_subject.res_subject ILIKE {{{parpatname}}}"]
         self._fillers, subqueries = {}, []
 
         for index, word in enumerate(self.words):
@@ -265,7 +265,7 @@ def _get_or_condition(self, service):
         base_queries = [
             " 1=ivo_hasword(res_description, {{{parname}}})",
             " 1=ivo_hasword(res_title, {{{parname}}})",
-            " res_subject ILIKE {{{parpatname}}}"]
+            " rr.res_subject.res_subject ILIKE {{{parpatname}}}"]
         self._fillers, conditions = {}, []
 
         for index, word in enumerate(self.words):
diff --git a/pyvo/registry/tests/test_regtap.py b/pyvo/registry/tests/test_regtap.py
index 67d52ca3e..a4d9bd802 100644
--- a/pyvo/registry/tests/test_regtap.py
+++ b/pyvo/registry/tests/test_regtap.py
@@ -67,7 +67,7 @@ def keywordstest_callback(request, context):
         assert "ivo_hasword(res_description, 'vizier')" in query
         assert "1=ivo_hasword(res_title, 'vizier')" in query
 
-        assert " res_subject ILIKE '%pulsar%'" in query
+        assert ".res_subject ILIKE '%pulsar%'" in query
         assert "1=ivo_hasword(res_description, 'pulsar')" in query
         assert "1=ivo_hasword(res_title, 'pulsar')" in query
 
@@ -86,7 +86,7 @@ def keywordstest_callback(request, context):
         data = dict(parse_qsl(request.body))
         query = data['QUERY']
 
-        assert "OR  res_subject ILIKE '%single%'" in query
+        assert "OR  rr.res_subject.res_subject ILIKE '%single%'" in query
         assert "1=ivo_hasword(res_description, 'single') " in query
         assert "1=ivo_hasword(res_title, 'single')" in query
 
diff --git a/pyvo/registry/tests/test_rtcons.py b/pyvo/registry/tests/test_rtcons.py
index 2b5ac14bf..a3dc61255 100644
--- a/pyvo/registry/tests/test_rtcons.py
+++ b/pyvo/registry/tests/test_rtcons.py
@@ -78,30 +78,30 @@ def test_basic(self):
         assert rtcons.Freetext("star").get_search_condition(FAKE_GAVO) == (
             "ivoid IN (SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_description, 'star') "
             "UNION SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_title, 'star') "
-            "UNION SELECT ivoid FROM rr.res_subject WHERE res_subject ILIKE '%star%')")
+            "UNION SELECT ivoid FROM rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%star%')")
 
     def test_interesting_literal(self):
         assert rtcons.Freetext("α Cen's planets").get_search_condition(FAKE_GAVO) == (
             "ivoid IN (SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_description, 'α Cen''s planets')"
             " UNION SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_title, 'α Cen''s planets')"
-            " UNION SELECT ivoid FROM rr.res_subject WHERE res_subject ILIKE '%α Cen''s planets%')")
+            " UNION SELECT ivoid FROM rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%α Cen''s planets%')")
 
     def test_multipleLiterals(self):
         assert rtcons.Freetext("term1", "term2"
             ).get_search_condition(FAKE_GAVO) == (
             "ivoid IN (SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_description, 'term1')"
             " UNION SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_title, 'term1')"
-            " UNION SELECT ivoid FROM rr.res_subject WHERE res_subject ILIKE '%term1%')"
+            " UNION SELECT ivoid FROM rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%term1%')"
         " AND "
         "ivoid IN (SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_description, 'term2')"
         " UNION SELECT ivoid FROM rr.resource WHERE 1=ivo_hasword(res_title, 'term2')"
-        " UNION SELECT ivoid FROM rr.res_subject WHERE res_subject ILIKE '%term2%')")
+        " UNION SELECT ivoid FROM rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%term2%')")
 
     def test_adaption_to_service(self):
         assert rtcons.Freetext("term1", "term2"
             ).get_search_condition(FAKE_PLAIN) == (
-            "( 1=ivo_hasword(res_description, 'term1') OR  1=ivo_hasword(res_title, 'term1') OR  res_subject ILIKE '%term1%')"
-            " AND ( 1=ivo_hasword(res_description, 'term2') OR  1=ivo_hasword(res_title, 'term2') OR  res_subject ILIKE '%term2%')")
+            "( 1=ivo_hasword(res_description, 'term1') OR  1=ivo_hasword(res_title, 'term1') OR  rr.res_subject.res_subject ILIKE '%term1%')"
+            " AND ( 1=ivo_hasword(res_description, 'term2') OR  1=ivo_hasword(res_title, 'term2') OR  rr.res_subject.res_subject ILIKE '%term2%')")
 
 
 class TestAuthorConstraint:
@@ -336,7 +336,6 @@ def test_no_temporal(self):
             == "stc_temporal missing on current RegTAP service")
 
 
-
 class TestWhereClauseBuilding:
     @staticmethod
     def where_clause_for(*args, **kwargs):
@@ -388,11 +387,11 @@ def test_with_legacy_keyword(self):
             '(ivoid IN (SELECT ivoid FROM rr.resource WHERE '
             "1=ivo_hasword(res_description, 'plain') UNION SELECT ivoid FROM rr.resource "
             "WHERE 1=ivo_hasword(res_title, 'plain') UNION SELECT ivoid FROM "
-            "rr.res_subject WHERE res_subject ILIKE '%plain%'))\n"
+            "rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%plain%'))\n"
             '  AND (ivoid IN (SELECT ivoid FROM rr.resource WHERE '
             "1=ivo_hasword(res_description, 'string') UNION SELECT ivoid FROM rr.resource "
             "WHERE 1=ivo_hasword(res_title, 'string') UNION SELECT ivoid FROM "
-            "rr.res_subject WHERE res_subject ILIKE '%string%'))")
+            "rr.res_subject WHERE rr.res_subject.res_subject ILIKE '%string%'))")
 
 
 class TestSelectClause: