diff --git a/gem_stanley_teacher.py b/gem_stanley_teacher.py
index 70500be7bf4ad6b836881db8d0b18aada144aacb..dff0fbc802d3e3e228c4a7a26086b297da5c195d 100644
--- a/gem_stanley_teacher.py
+++ b/gem_stanley_teacher.py
@@ -108,14 +108,9 @@ class GEMStanleyGurobiTeacher(GurobiTeacherBase):
         super().__init__(name=name,
                          state_dim=3, perc_dim=2, ctrl_dim=1, norm_ord=norm_ord)
 
-    def is_positive_example(self, ex) -> Optional[bool]:
+    def is_positive_example(self, ex) -> bool:
         assert len(ex) == self.state_dim + self.perc_dim
 
-        state_arr = np.asfarray(ex[0:self.state_dim])
-        if not (np.all(self._old_state.lb <= state_arr) and
-                np.all(state_arr <= self._old_state.ub)):
-            return None
-
         def g(cte, phi):
             error = phi + np.arctan(K_P*cte/FORWARD_VEL)
             steer = np.clip(error, -STEERING_LIM, STEERING_LIM)