diff --git a/stix2/v20/common.py b/stix2/v20/common.py
index 0a0cabc..682d4b3 100644
--- a/stix2/v20/common.py
+++ b/stix2/v20/common.py
@@ -128,6 +128,16 @@ class MarkingDefinition(_STIXBase, _MarkingsMixin):
                 self._properties.update([
                     ('created', TimestampProperty(default=lambda: NOW, precision='millisecond')),
                 ])
+            else:
+                try:
+                    #statement instances will match the precision given
+                    if kwargs['created'].rfind('.') != -1:
+                        self._properties = copy.deepcopy(self._properties)
+                        self._properties.update([
+                            ('created', TimestampProperty(default=lambda: NOW, precision='millisecond')),
+                        ])
+                except AttributeError:
+                    pass
 
             if not isinstance(kwargs['definition'], marking_type):
                 defn = _get_dict(kwargs['definition'])
diff --git a/stix2/v21/common.py b/stix2/v21/common.py
index 13d0ff6..881eced 100644
--- a/stix2/v21/common.py
+++ b/stix2/v21/common.py
@@ -146,7 +146,7 @@ class MarkingDefinition(_STIXBase, _MarkingsMixin):
         ('spec_version', StringProperty(fixed='2.1')),
         ('id', IDProperty(_type)),
         ('created_by_ref', ReferenceProperty(type='identity')),
-        ('created', TimestampProperty(default=lambda: NOW)),
+        ('created', TimestampProperty(default=lambda: NOW, precision='millisecond')),
         ('external_references', ListProperty(ExternalReference)),
         ('object_marking_refs', ListProperty(ReferenceProperty(type='marking-definition'))),
         ('granular_markings', ListProperty(GranularMarking)),
@@ -162,13 +162,6 @@ class MarkingDefinition(_STIXBase, _MarkingsMixin):
             except KeyError:
                 raise ValueError("definition_type must be a valid marking type")
 
-            if marking_type == TLPMarking:
-                # TLP instances in the spec have millisecond precision unlike other markings
-                self._properties = copy.deepcopy(self._properties)
-                self._properties.update([
-                    ('created', TimestampProperty(default=lambda: NOW, precision='millisecond')),
-                ])
-
             if not isinstance(kwargs['definition'], marking_type):
                 defn = _get_dict(kwargs['definition'])
                 kwargs['definition'] = marking_type(**defn)