diff --git a/stix2/markings/utils.py b/stix2/markings/utils.py
index b1c103b..41516cc 100644
--- a/stix2/markings/utils.py
+++ b/stix2/markings/utils.py
@@ -271,8 +271,8 @@ def check_tlp_marking(marking_obj, spec_version):
             else:
                 w = (
                     '{"created": "2017-01-20T00:00:00.000Z", "definition": {"tlp": "white"}, "definition_type": "tlp",'
-                    ' "id": "marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9", "type": "marking-definition",'
-                    ' "spec_version": "2.1"}'
+                    ' "id": "marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9", "name": "TLP:WHITE",'
+                    ' "type": "marking-definition", "spec_version": "2.1"}'
                 )
             if marking_obj["id"] != "marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9":
                 raise exceptions.TLPMarkingDefinitionError(marking_obj["id"], w)
@@ -288,8 +288,8 @@ def check_tlp_marking(marking_obj, spec_version):
             else:
                 g = (
                     '{"created": "2017-01-20T00:00:00.000Z", "definition": {"tlp": "green"}, "definition_type": "tlp",'
-                    ' "id": "marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da", "type": "marking-definition",'
-                    ' "spec_version": "2.1"}'
+                    ' "id": "marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da", "name": "TLP:GREEN",'
+                    ' "type": "marking-definition", "spec_version": "2.1"}'
                 )
             if marking_obj["id"] != "marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da":
                 raise exceptions.TLPMarkingDefinitionError(marking_obj["id"], g)
@@ -305,8 +305,8 @@ def check_tlp_marking(marking_obj, spec_version):
             else:
                 a = (
                     '{"created": "2017-01-20T00:00:00.000Z", "definition": {"tlp": "amber"}, "definition_type": "tlp",'
-                    ' "id": "marking-definition--f88d31f6-486f-44da-b317-01333bde0b82", "type": "marking-definition",'
-                    ' "spec_version": "2.1"}'
+                    ' "id": "marking-definition--f88d31f6-486f-44da-b317-01333bde0b82", "name": "TLP:AMBER",'
+                    ' "type": "marking-definition", "spec_version": "2.1"}'
                 )
             if marking_obj["id"] != "marking-definition--f88d31f6-486f-44da-b317-01333bde0b82":
                 raise exceptions.TLPMarkingDefinitionError(marking_obj["id"], a)
@@ -322,8 +322,8 @@ def check_tlp_marking(marking_obj, spec_version):
             else:
                 r = (
                     '{"created": "2017-01-20T00:00:00.000Z", "definition": {"tlp": "red"}, "definition_type": "tlp",'
-                    ' "id": "marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed", "type": "marking-definition",'
-                    ' "spec_version": "2.1"}'
+                    ' "id": "marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed", "name": "TLP:RED",'
+                    ' "type": "marking-definition", "spec_version": "2.1"}'
                 )
             if marking_obj["id"] != "marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed":
                 raise exceptions.TLPMarkingDefinitionError(marking_obj["id"], r)
diff --git a/stix2/v21/common.py b/stix2/v21/common.py
index 4a71308..cf3a3b3 100644
--- a/stix2/v21/common.py
+++ b/stix2/v21/common.py
@@ -150,6 +150,7 @@ class MarkingDefinition(_STIXBase, _MarkingsMixin):
         ('object_marking_refs', ListProperty(ReferenceProperty(valid_types='marking-definition', spec_version='2.1'))),
         ('granular_markings', ListProperty(GranularMarking)),
         ('definition_type', StringProperty(required=True)),
+        ('name', StringProperty()),
         ('definition', MarkingProperty(required=True)),
     ])
 
@@ -207,6 +208,7 @@ TLP_WHITE = MarkingDefinition(
     id='marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9',
     created='2017-01-20T00:00:00.000Z',
     definition_type='tlp',
+    name='TLP:WHITE',
     definition=TLPMarking(tlp='white'),
 )
 
@@ -214,6 +216,7 @@ TLP_GREEN = MarkingDefinition(
     id='marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da',
     created='2017-01-20T00:00:00.000Z',
     definition_type='tlp',
+    name='TLP:GREEN',
     definition=TLPMarking(tlp='green'),
 )
 
@@ -221,6 +224,7 @@ TLP_AMBER = MarkingDefinition(
     id='marking-definition--f88d31f6-486f-44da-b317-01333bde0b82',
     created='2017-01-20T00:00:00.000Z',
     definition_type='tlp',
+    name='TLP:AMBER',
     definition=TLPMarking(tlp='amber'),
 )
 
@@ -228,5 +232,6 @@ TLP_RED = MarkingDefinition(
     id='marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed',
     created='2017-01-20T00:00:00.000Z',
     definition_type='tlp',
+    name='TLP:RED',
     definition=TLPMarking(tlp='red'),
 )

`name` field missing from MarkingDefinition object
Super quick one: MarkingDefinition object should have an optional `name` field as per the current spec. Believe it needs adding to `common.py`.
diff --git a/stix2/test/v21/test_marking_definition.py b/stix2/test/v21/test_marking_definition.py
index c497e99..232bdf2 100644
--- a/stix2/test/v21/test_marking_definition.py
+++ b/stix2/test/v21/test_marking_definition.py
@@ -12,6 +12,7 @@ def test_bad_id_marking_tlp_white():
         MarkingDefinition(
             id='marking-definition--4c9faac1-3558-43d2-919e-95c88d3bc332',
             definition_type='tlp',
+            name='TLP:WHITE',
             definition=TLPMarking(tlp='white'),
         )
 
@@ -21,6 +22,7 @@ def test_bad_id_marking_tlp_green():
         MarkingDefinition(
             id='marking-definition--93023361-d3cf-4666-bca2-8c017948dc3d',
             definition_type='tlp',
+            name='TLP:GREEN',
             definition=TLPMarking(tlp='green'),
         )
 
@@ -30,6 +32,7 @@ def test_bad_id_marking_tlp_amber():
         MarkingDefinition(
             id='marking-definition--05e32101-a940-42ba-8fe9-39283b999ce4',
             definition_type='tlp',
+            name='TLP:AMBER',
             definition=TLPMarking(tlp='amber'),
         )
 
@@ -39,6 +42,7 @@ def test_bad_id_marking_tlp_red():
         MarkingDefinition(
             id='marking-definition--9eceb00c-c158-43f4-87f8-1e3648de17e2',
             definition_type='tlp',
+            name='TLP:RED',
             definition=TLPMarking(tlp='red'),
         )
 
@@ -48,6 +52,7 @@ def test_bad_created_marking_tlp_white():
         MarkingDefinition(
             id='marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9',
             definition_type='tlp',
+            name='TLP:WHITE',
             definition=TLPMarking(tlp='white'),
         )
 
@@ -57,6 +62,7 @@ def test_bad_created_marking_tlp_green():
         MarkingDefinition(
             id='marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da',
             definition_type='tlp',
+            name='TLP:GREEN',
             definition=TLPMarking(tlp='green'),
         )
 
@@ -66,6 +72,7 @@ def test_bad_created_marking_tlp_amber():
         MarkingDefinition(
             id='marking-definition--f88d31f6-486f-44da-b317-01333bde0b82',
             definition_type='tlp',
+            name='TLP:AMBER',
             definition=TLPMarking(tlp='amber'),
         )
 
@@ -75,6 +82,7 @@ def test_bad_created_marking_tlp_red():
         MarkingDefinition(
             id='marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed',
             definition_type='tlp',
+            name='TLP:RED',
             definition=TLPMarking(tlp='red'),
         )
 
@@ -86,6 +94,7 @@ def test_successful_tlp_white():
         id='marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9',
         created='2017-01-20T00:00:00.000Z',
         definition_type='tlp',
+        name='TLP:WHITE',
         definition=TLPMarking(tlp='white'),
     )
 
@@ -97,6 +106,7 @@ def test_successful_tlp_green():
         id='marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da',
         created='2017-01-20T00:00:00.000Z',
         definition_type='tlp',
+        name='TLP:GREEN',
         definition=TLPMarking(tlp='green'),
     )
 
@@ -108,6 +118,7 @@ def test_successful_tlp_amber():
         id='marking-definition--f88d31f6-486f-44da-b317-01333bde0b82',
         created='2017-01-20T00:00:00.000Z',
         definition_type='tlp',
+        name='TLP:AMBER',
         definition=TLPMarking(tlp='amber'),
     )
 
@@ -119,6 +130,7 @@ def test_successful_tlp_red():
         id='marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed',
         created='2017-01-20T00:00:00.000Z',
         definition_type='tlp',
+        name='TLP:RED',
         definition=TLPMarking(tlp='red'),
     )
 
diff --git a/stix2/test/v21/test_markings.py b/stix2/test/v21/test_markings.py
index 1f9f5e8..a2fca51 100644
--- a/stix2/test/v21/test_markings.py
+++ b/stix2/test/v21/test_markings.py
@@ -16,6 +16,7 @@ EXPECTED_TLP_MARKING_DEFINITION = """{
     "id": "marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9",
     "created": "2017-01-20T00:00:00.000Z",
     "definition_type": "tlp",
+    "name": "TLP:WHITE",
     "definition": {
         "tlp": "white"
     }

pip install -e .[dev]
parse_log_pytest
requirements.txt
pytest pytest-cov pytest-xdist pytest-mock pytest-asyncio
apt-get update apt-get install -y gcc
3.7
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
alabaster==0.7.13
antlr4-python3-runtime==4.9.3
attrs==24.2.0
Babel==2.14.0
backcall==0.2.0
beautifulsoup4==4.13.3
bleach==6.0.0
bump2version==1.0.1
bumpversion==0.6.0
cachetools==5.5.2
certifi @ file:///croot/certifi_1671487769961/work/certifi
cfgv==3.3.1
chardet==5.2.0
charset-normalizer==3.4.1
colorama==0.4.6
coverage==7.2.7
decorator==5.1.1
defusedxml==0.7.1
distlib==0.3.9
docutils==0.17.1
entrypoints==0.4
exceptiongroup==1.2.2
execnet==2.0.2
fastjsonschema==2.21.1
filelock==3.12.2
identify==2.5.24
idna==3.10
imagesize==1.4.1
importlib-metadata==6.7.0
importlib-resources==5.12.0
iniconfig==2.0.0
ipython==7.34.0
jedi==0.19.2
Jinja2==3.1.6
jsonschema==4.17.3
jupyter_client==7.4.9
jupyter_core==4.12.0
jupyterlab-pygments==0.2.2
MarkupSafe==2.1.5
matplotlib-inline==0.1.6
mistune==3.0.2
nbclient==0.7.4
nbconvert==7.6.0
nbformat==5.8.0
nbsphinx==0.4.3
nest-asyncio==1.6.0
nodeenv==1.9.1
packaging==24.0
pandocfilters==1.5.1
parso==0.8.4
pexpect==4.9.0
pickleshare==0.7.5
pkgutil_resolve_name==1.3.10
platformdirs==4.0.0
pluggy==1.2.0
pre-commit==2.21.0
prompt_toolkit==3.0.48
ptyprocess==0.7.0
Pygments==2.17.2
pyproject-api==1.5.3
pyrsistent==0.19.3
pytest==7.4.4
pytest-asyncio==0.21.2
pytest-cov==4.1.0
pytest-mock==3.11.1
pytest-xdist==3.5.0
python-dateutil==2.9.0.post0
pytz==2025.2
PyYAML==6.0.1
pyzmq==26.2.1
requests==2.31.0
simplejson==3.20.1
six==1.17.0
snowballstemmer==2.2.0
soupsieve==2.4.1
Sphinx==1.8.6
sphinx-prompt==1.5.0
sphinxcontrib-serializinghtml==1.1.5
sphinxcontrib-websupport==1.2.4
-e git+https://github.com/oasis-open/cti-python-stix2.git@0af1f442c0cb6e30132174b5b657a6a35ef78a08#egg=stix2
stix2-patterns==2.0.0
tinycss2==1.2.1
tomli==2.0.1
tornado==6.2
tox==4.8.0
traitlets==5.9.0
typing_extensions==4.7.1
urllib3==2.0.7
virtualenv==20.26.6
wcwidth==0.2.13
webencodings==0.5.1
zipp==3.15.0

name: cti-python-stix2
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2022.12.7=py37h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.4.4=h6a678d5_1
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=22.3.1=py37h06a4308_0
  - python=3.7.16=h7a1cb2a_0
  - readline=8.2=h5eee18b_0
  - setuptools=65.6.3=py37h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.38.4=py37h06a4308_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - alabaster==0.7.13
      - antlr4-python3-runtime==4.9.3
      - attrs==24.2.0
      - babel==2.14.0
      - backcall==0.2.0
      - beautifulsoup4==4.13.3
      - bleach==6.0.0
      - bump2version==1.0.1
      - bumpversion==0.6.0
      - cachetools==5.5.2
      - cfgv==3.3.1
      - chardet==5.2.0
      - charset-normalizer==3.4.1
      - colorama==0.4.6
      - coverage==7.2.7
      - decorator==5.1.1
      - defusedxml==0.7.1
      - distlib==0.3.9
      - docutils==0.17.1
      - entrypoints==0.4
      - exceptiongroup==1.2.2
      - execnet==2.0.2
      - fastjsonschema==2.21.1
      - filelock==3.12.2
      - identify==2.5.24
      - idna==3.10
      - imagesize==1.4.1
      - importlib-metadata==6.7.0
      - importlib-resources==5.12.0
      - iniconfig==2.0.0
      - ipython==7.34.0
      - jedi==0.19.2
      - jinja2==3.1.6
      - jsonschema==4.17.3
      - jupyter-client==7.4.9
      - jupyter-core==4.12.0
      - jupyterlab-pygments==0.2.2
      - markupsafe==2.1.5
      - matplotlib-inline==0.1.6
      - mistune==3.0.2
      - nbclient==0.7.4
      - nbconvert==7.6.0
      - nbformat==5.8.0
      - nbsphinx==0.4.3
      - nest-asyncio==1.6.0
      - nodeenv==1.9.1
      - packaging==24.0
      - pandocfilters==1.5.1
      - parso==0.8.4
      - pexpect==4.9.0
      - pickleshare==0.7.5
      - pkgutil-resolve-name==1.3.10
      - platformdirs==4.0.0
      - pluggy==1.2.0
      - pre-commit==2.21.0
      - prompt-toolkit==3.0.48
      - ptyprocess==0.7.0
      - pygments==2.17.2
      - pyproject-api==1.5.3
      - pyrsistent==0.19.3
      - pytest==7.4.4
      - pytest-asyncio==0.21.2
      - pytest-cov==4.1.0
      - pytest-mock==3.11.1
      - pytest-xdist==3.5.0
      - python-dateutil==2.9.0.post0
      - pytz==2025.2
      - pyyaml==6.0.1
      - pyzmq==26.2.1
      - requests==2.31.0
      - simplejson==3.20.1
      - six==1.17.0
      - snowballstemmer==2.2.0
      - soupsieve==2.4.1
      - sphinx==1.8.6
      - sphinx-prompt==1.5.0
      - sphinxcontrib-serializinghtml==1.1.5
      - sphinxcontrib-websupport==1.2.4
      - stix2-patterns==2.0.0
      - tinycss2==1.2.1
      - tomli==2.0.1
      - tornado==6.2
      - tox==4.8.0
      - traitlets==5.9.0
      - typing-extensions==4.7.1
      - urllib3==2.0.7
      - virtualenv==20.26.6
      - wcwidth==0.2.13
      - webencodings==0.5.1
      - zipp==3.15.0
prefix: /opt/conda/envs/cti-python-stix2

stix2/test/v21/test_marking_definition.py::test_bad_id_marking_tlp_white stix2/test/v21/test_marking_definition.py::test_bad_id_marking_tlp_green stix2/test/v21/test_marking_definition.py::test_bad_id_marking_tlp_amber stix2/test/v21/test_marking_definition.py::test_bad_id_marking_tlp_red stix2/test/v21/test_marking_definition.py::test_bad_created_marking_tlp_white stix2/test/v21/test_marking_definition.py::test_bad_created_marking_tlp_green stix2/test/v21/test_marking_definition.py::test_bad_created_marking_tlp_amber stix2/test/v21/test_marking_definition.py::test_bad_created_marking_tlp_red stix2/test/v21/test_marking_definition.py::test_successful_tlp_white stix2/test/v21/test_marking_definition.py::test_successful_tlp_green stix2/test/v21/test_marking_definition.py::test_successful_tlp_amber stix2/test/v21/test_marking_definition.py::test_successful_tlp_red stix2/test/v21/test_markings.py::test_marking_def_example_with_tlp stix2/test/v21/test_markings.py::test_parse_marking_definition[{\n
stix2/test/v21/test_marking_definition.py::test_unknown_tlp_marking stix2/test/v21/test_markings.py::test_marking_def_example_with_statement_positional_argument stix2/test/v21/test_markings.py::test_marking_def_example_with_kwargs_statement stix2/test/v21/test_markings.py::test_marking_def_invalid_type stix2/test/v21/test_markings.py::test_campaign_with_markings_example stix2/test/v21/test_markings.py::test_granular_example stix2/test/v21/test_markings.py::test_granular_example_with_bad_selector stix2/test/v21/test_markings.py::test_campaign_with_granular_markings_example stix2/test/v21/test_markings.py::test_parse_marking_definition[data1] stix2/test/v21/test_markings.py::test_registered_custom_marking stix2/test/v21/test_markings.py::test_registered_custom_marking_raises_exception stix2/test/v21/test_markings.py::test_not_registered_marking_raises_exception stix2/test/v21/test_markings.py::test_marking_wrong_type_construction stix2/test/v21/test_markings.py::test_campaign_add_markings stix2/test/v21/test_markings.py::test_campaign_with_granular_lang_markings_example
stix2/v21/common.py stix2/markings/utils.py
stix2/v21/common.py stix2/markings/utils.py