diff --git a/src/vars_gridview/lib/m3/query.py b/src/vars_gridview/lib/m3/query.py
index c811250..d843793 100644
--- a/src/vars_gridview/lib/m3/query.py
+++ b/src/vars_gridview/lib/m3/query.py
@@ -16,6 +16,7 @@ class QueryConstraint:
     in_: list[str] | None = None
     isnull: bool | None = None
     like: str | None = None
+    notlike: str | None = None
     max: float | None = None
     min: float | None = None
     minmax: list[float] | None = None
@@ -29,6 +30,7 @@ def to_dict(self, skip_null: bool = True) -> dict:
             "in": self.in_,
             "isnull": self.isnull,
             "like": self.like,
+            "notlike": self.notlike,
             "max": self.max,
             "min": self.min,
             "minmax": self.minmax,
diff --git a/src/vars_gridview/ui/QueryDialog.py b/src/vars_gridview/ui/QueryDialog.py
index 30755cd..0ad6ad2 100644
--- a/src/vars_gridview/ui/QueryDialog.py
+++ b/src/vars_gridview/ui/QueryDialog.py
@@ -199,6 +199,19 @@ def __str__(self) -> str:
         return "Verified"
 
 
+class NotVerifiedConstraintResult(BaseResult):
+    """
+    A constraint result that creates a constraint to check if the verifier field is NOT present (i.e., not verified).
+    """
+
+    @property
+    def constraints(self) -> Iterable[QueryConstraint]:
+        yield QueryConstraint(column="link_value", notlike='%"verifier":%')
+
+    def __str__(self) -> str:
+        return "Not Verified"
+
+
 class ConceptInConstraintResult(InConstraintResult):
     """
     A constraint result that creates an IN constraint for a list of concepts.
@@ -880,6 +893,7 @@ def _create_default_filters(self) -> List[BaseFilter]:
             GeneratorFilter(self, "Generator", "generator", prompt="Generator"),
             VerifierFilter(self, "Verifier", "verifier", prompt="Verifier"),
             FunctionalFilter(self, "Verified", lambda: VerifiedConstraintResult()),
+            FunctionalFilter(self, "Not Verified", lambda: NotVerifiedConstraintResult()),
         ]
 
     @pyqtSlot()
diff --git a/tests/test_query_constraints.py b/tests/test_query_constraints.py
index a8cf84e..b2565da 100644
--- a/tests/test_query_constraints.py
+++ b/tests/test_query_constraints.py
@@ -51,5 +51,38 @@ def test_constraint_to_dict_skip_null(self):
         self.assertNotIn("equals", result_dict)
 
 
+class TestLikeConstraints(unittest.TestCase):
+    """Test the like and notlike constraints functionality."""
+
+    def test_like_constraint(self):
+        """Test that a like constraint is created correctly."""
+        constraint = QueryConstraint(column="link_value", like='%"verifier":%')
+        result_dict = constraint.to_dict()
+        
+        self.assertEqual(result_dict["column"], "link_value")
+        self.assertEqual(result_dict["like"], '%"verifier":%')
+        self.assertNotIn("notlike", result_dict)
+
+    def test_notlike_constraint(self):
+        """Test that a notlike constraint is created correctly."""
+        constraint = QueryConstraint(column="link_value", notlike='%"verifier":%')
+        result_dict = constraint.to_dict()
+        
+        self.assertEqual(result_dict["column"], "link_value")
+        self.assertEqual(result_dict["notlike"], '%"verifier":%')
+        self.assertNotIn("like", result_dict)
+
+    def test_notlike_skip_null(self):
+        """Test that null notlike value is excluded when skip_null=True."""
+        constraint = QueryConstraint(
+            column="link_value",
+            notlike=None
+        )
+        result_dict = constraint.to_dict(skip_null=True)
+        
+        self.assertIn("column", result_dict)
+        self.assertNotIn("notlike", result_dict)
+
+
 if __name__ == "__main__":
     unittest.main()