diff --git a/python/helpers/pydev/pydevd.py b/python/helpers/pydev/pydevd.py
index d727cb1397aa..032e117597de 100644
--- a/python/helpers/pydev/pydevd.py
+++ b/python/helpers/pydev/pydevd.py
@@ -393,7 +393,7 @@ class PyDB:
         return self.plugin
 
     def not_in_scope(self, filename):
-        return pydevd_utils.is_in_project_roots(filename)
+        return pydevd_utils.not_in_project_roots(filename)
 
     def first_appearance_in_scope(self, trace):
         if trace is None or self.not_in_scope(trace.tb_frame.f_code.co_filename):
diff --git a/python/helpers/pydev/pydevd_signature.py b/python/helpers/pydev/pydevd_signature.py
index a63ca8e032f7..653837912777 100644
--- a/python/helpers/pydev/pydevd_signature.py
+++ b/python/helpers/pydev/pydevd_signature.py
@@ -32,9 +32,10 @@ class Signature(object):
 class SignatureFactory(object):
     def __init__(self):
         self._caller_cache = {}
+        self._ignore_module_name = ('__main__', '__builtin__', 'builtins')
 
     def is_in_scope(self, filename):
-        return pydevd_utils.is_in_project_roots(filename)
+        return not pydevd_utils.not_in_project_roots(filename)
 
     def create_signature(self, frame):
         try:
@@ -50,7 +51,7 @@ class SignatureFactory(object):
                     tp = locals[name].__class__
                     class_name = tp.__name__
 
-                if hasattr(tp, '__module__') and tp.__module__ and tp.__module__ != '__main__':
+                if hasattr(tp, '__module__') and tp.__module__ and tp.__module__ not in self._ignore_module_name:
                     class_name = "%s.%s"%(tp.__module__, class_name)
 
                 res.add_arg(name, class_name)
diff --git a/python/helpers/pydev/pydevd_utils.py b/python/helpers/pydev/pydevd_utils.py
index 34fc24cf37b0..eaabb5c46211 100644
--- a/python/helpers/pydev/pydevd_utils.py
+++ b/python/helpers/pydev/pydevd_utils.py
@@ -128,7 +128,7 @@ def _get_project_roots(project_roots_cache=[]):
     return project_roots_cache[-1] # returns the project roots with case normalized
 
 
-def is_in_project_roots(filename, filename_to_not_in_scope_cache={}):
+def not_in_project_roots(filename, filename_to_not_in_scope_cache={}):
     # Note: the filename_to_not_in_scope_cache is the same instance among the many calls to the method
     try:
         return filename_to_not_in_scope_cache[filename]