diff --git a/stix2/v20/bundle.py b/stix2/v20/bundle.py
index 81df0f6..39e0635 100644
--- a/stix2/v20/bundle.py
+++ b/stix2/v20/bundle.py
@@ -2,8 +2,8 @@ from collections import OrderedDict
 
 from stix2 import parse
 from stix2.base import _STIXBase
-from stix2.properties import (IDProperty, ListProperty, Property,
-                              StringProperty, TypeProperty)
+from .properties import (IDProperty, ListProperty, Property,
+                         StringProperty, TypeProperty)
 from stix2.utils import _get_dict, get_class_hierarchy_names
 
 
diff --git a/stix2/v20/common.py b/stix2/v20/common.py
index 44a5267..7341285 100644
--- a/stix2/v20/common.py
+++ b/stix2/v20/common.py
@@ -4,9 +4,9 @@ from collections import OrderedDict
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (HashesProperty, IDProperty, ListProperty, Property,
-                          ReferenceProperty, SelectorProperty, StringProperty,
-                          TimestampProperty, TypeProperty)
+from .properties import (HashesProperty, IDProperty, ListProperty, Property,
+                         ReferenceProperty, SelectorProperty, StringProperty,
+                         TimestampProperty, TypeProperty)
 from ..utils import NOW, _get_dict
 
 
diff --git a/stix2/v20/observables.py b/stix2/v20/observables.py
index 659929b..62db362 100644
--- a/stix2/v20/observables.py
+++ b/stix2/v20/observables.py
@@ -12,11 +12,11 @@ import re
 from ..base import _Extension, _Observable, _STIXBase
 from ..exceptions import (AtLeastOnePropertyError, CustomContentError,
                           DependentPropertiesError, ParseError)
-from ..properties import (BinaryProperty, BooleanProperty, DictionaryProperty,
-                          EmbeddedObjectProperty, EnumProperty, FloatProperty,
-                          HashesProperty, HexProperty, IntegerProperty,
-                          ListProperty, ObjectReferenceProperty, Property,
-                          StringProperty, TimestampProperty, TypeProperty)
+from .properties import (BinaryProperty, BooleanProperty, DictionaryProperty,
+                         EmbeddedObjectProperty, EnumProperty, FloatProperty,
+                         HashesProperty, HexProperty, IntegerProperty,
+                         ListProperty, ObjectReferenceProperty, Property,
+                         StringProperty, TimestampProperty, TypeProperty)
 from ..utils import TYPE_REGEX, _get_dict
 
 
diff --git a/stix2/v20/properties.py b/stix2/v20/properties.py
index 39d383a..ff6f9f0 100644
--- a/stix2/v20/properties.py
+++ b/stix2/v20/properties.py
@@ -10,9 +10,9 @@ import uuid
 from six import string_types, text_type
 from stix2patterns.validator import run_validator
 
-from .base import _STIXBase
-from .exceptions import DictionaryKeyError
-from .utils import _get_dict, parse_into_datetime
+from stix2.base import _STIXBase
+from stix2.exceptions import DictionaryKeyError
+from stix2.utils import _get_dict, parse_into_datetime
 
 
 class Property(object):
diff --git a/stix2/v20/sdo.py b/stix2/v20/sdo.py
index abe7df4..c0a3be6 100644
--- a/stix2/v20/sdo.py
+++ b/stix2/v20/sdo.py
@@ -8,9 +8,9 @@ import stix2
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (BooleanProperty, IDProperty, IntegerProperty,
-                          ListProperty, PatternProperty, ReferenceProperty,
-                          StringProperty, TimestampProperty, TypeProperty)
+from .properties import (BooleanProperty, IDProperty, IntegerProperty,
+                         ListProperty, PatternProperty, ReferenceProperty,
+                         StringProperty, TimestampProperty, TypeProperty)
 from ..utils import NOW, TYPE_REGEX
 from .common import ExternalReference, GranularMarking, KillChainPhase
 from .observables import ObservableProperty
diff --git a/stix2/v20/sro.py b/stix2/v20/sro.py
index e488229..7559f5b 100644
--- a/stix2/v20/sro.py
+++ b/stix2/v20/sro.py
@@ -4,9 +4,9 @@ from collections import OrderedDict
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (BooleanProperty, IDProperty, IntegerProperty,
-                          ListProperty, ReferenceProperty, StringProperty,
-                          TimestampProperty, TypeProperty)
+from .properties import (BooleanProperty, IDProperty, IntegerProperty,
+                         ListProperty, ReferenceProperty, StringProperty,
+                         TimestampProperty, TypeProperty)
 from ..utils import NOW
 from .common import ExternalReference, GranularMarking
 
diff --git a/stix2/v21/bundle.py b/stix2/v21/bundle.py
index 6c20923..5ecb6fc 100644
--- a/stix2/v21/bundle.py
+++ b/stix2/v21/bundle.py
@@ -2,7 +2,7 @@ from collections import OrderedDict
 
 from stix2 import parse
 from stix2.base import _STIXBase
-from stix2.properties import IDProperty, ListProperty, Property, TypeProperty
+from .properties import IDProperty, ListProperty, Property, TypeProperty
 from stix2.utils import _get_dict, get_class_hierarchy_names
 
 
diff --git a/stix2/v21/common.py b/stix2/v21/common.py
index f31eeef..cb740fc 100644
--- a/stix2/v21/common.py
+++ b/stix2/v21/common.py
@@ -4,10 +4,10 @@ from collections import OrderedDict
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (BooleanProperty, DictionaryProperty, HashesProperty,
-                          IDProperty, ListProperty, Property,
-                          ReferenceProperty, SelectorProperty, StringProperty,
-                          TimestampProperty, TypeProperty)
+from .properties import (BooleanProperty, DictionaryProperty, HashesProperty,
+                         IDProperty, ListProperty, Property,
+                         ReferenceProperty, SelectorProperty, StringProperty,
+                         TimestampProperty, TypeProperty)
 from ..utils import NOW, _get_dict
 
 
diff --git a/stix2/v21/observables.py b/stix2/v21/observables.py
index 2da80b0..e808e90 100644
--- a/stix2/v21/observables.py
+++ b/stix2/v21/observables.py
@@ -12,11 +12,11 @@ import re
 from ..base import _Extension, _Observable, _STIXBase
 from ..exceptions import (AtLeastOnePropertyError, CustomContentError,
                           DependentPropertiesError, ParseError)
-from ..properties import (BinaryProperty, BooleanProperty, DictionaryProperty,
-                          EmbeddedObjectProperty, EnumProperty, FloatProperty,
-                          HashesProperty, HexProperty, IntegerProperty,
-                          ListProperty, ObjectReferenceProperty, Property,
-                          StringProperty, TimestampProperty, TypeProperty)
+from .properties import (BinaryProperty, BooleanProperty, DictionaryProperty,
+                         EmbeddedObjectProperty, EnumProperty, FloatProperty,
+                         HashesProperty, HexProperty, IntegerProperty,
+                         ListProperty, ObjectReferenceProperty, Property,
+                         StringProperty, TimestampProperty, TypeProperty)
 from ..utils import TYPE_REGEX, _get_dict
 
 
diff --git a/stix2/v21/properties.py b/stix2/v21/properties.py
index 796a5cb..82ca784 100644
--- a/stix2/v21/properties.py
+++ b/stix2/v21/properties.py
@@ -10,9 +10,9 @@ import uuid
 from six import string_types, text_type
 from stix2patterns.validator import run_validator
 
-from .base import _STIXBase
-from .exceptions import DictionaryKeyError
-from .utils import _get_dict, parse_into_datetime
+from stix2.base import _STIXBase
+from stix2.exceptions import DictionaryKeyError
+from stix2.utils import _get_dict, parse_into_datetime
 
 
 class Property(object):
diff --git a/stix2/v21/sdo.py b/stix2/v21/sdo.py
index 1207a22..f3d3510 100644
--- a/stix2/v21/sdo.py
+++ b/stix2/v21/sdo.py
@@ -7,11 +7,11 @@ import stix2
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (BooleanProperty, DictionaryProperty,
-                          EmbeddedObjectProperty, EnumProperty, FloatProperty,
-                          IDProperty, IntegerProperty, ListProperty,
-                          PatternProperty, ReferenceProperty, StringProperty,
-                          TimestampProperty, TypeProperty)
+from .properties import (BooleanProperty, DictionaryProperty,
+                         EmbeddedObjectProperty, EnumProperty, FloatProperty,
+                         IDProperty, IntegerProperty, ListProperty,
+                         PatternProperty, ReferenceProperty, StringProperty,
+                         TimestampProperty, TypeProperty)
 from ..utils import NOW, TYPE_REGEX
 from .common import ExternalReference, GranularMarking, KillChainPhase
 from .observables import ObservableProperty
diff --git a/stix2/v21/sro.py b/stix2/v21/sro.py
index 7565bbb..6fadb5f 100644
--- a/stix2/v21/sro.py
+++ b/stix2/v21/sro.py
@@ -4,9 +4,9 @@ from collections import OrderedDict
 
 from ..base import _STIXBase
 from ..markings import _MarkingsMixin
-from ..properties import (BooleanProperty, IDProperty, IntegerProperty,
-                          ListProperty, ReferenceProperty, StringProperty,
-                          TimestampProperty, TypeProperty)
+from .properties import (BooleanProperty, IDProperty, IntegerProperty,
+                         ListProperty, ReferenceProperty, StringProperty,
+                         TimestampProperty, TypeProperty)
 from ..utils import NOW
 from .common import ExternalReference, GranularMarking