diff --git a/cms/djangoapps/contentstore/views/tests/test_block.py b/cms/djangoapps/contentstore/views/tests/test_block.py
index c8ac9b89dc2d..742db9f5bc20 100644
--- a/cms/djangoapps/contentstore/views/tests/test_block.py
+++ b/cms/djangoapps/contentstore/views/tests/test_block.py
@@ -73,6 +73,7 @@
 from common.djangoapps.xblock_django.user_service import DjangoXBlockUserService
 from lms.djangoapps.lms_xblock.mixin import NONSENSICAL_ACCESS_RESTRICTION
 from openedx.core.djangoapps.discussions.models import DiscussionsConfiguration
+from openedx.core.djangoapps.content_tagging import api as tagging_api
 
 from ..component import component_handler, get_component_templates
 from cms.djangoapps.contentstore.xblock_storage_handlers.view_handlers import (
@@ -1106,6 +1107,57 @@ def test_duplicate_library_content_block(self):  # pylint: disable=too-many-stat
         assert dupe_html_2.display_name == "HTML 2 Title (Lib Update)"
         assert dupe_html_2.data == "HTML 2 Content (Lib Update)"
 
+    def test_duplicate_tags(self):
+        """
+        Test that duplicating a tagged XBlock also duplicates its content tags.
+        """
+        source_course = CourseFactory()
+        user = UserFactory.create()
+        source_chapter = BlockFactory(
+            parent=source_course, category="chapter", display_name="Source Chapter"
+        )
+        source_block = BlockFactory(parent=source_chapter, category="html", display_name="Child")
+
+        # Create a couple of taxonomies with tags
+        taxonomyA = tagging_api.create_taxonomy(name="A", export_id="A")
+        taxonomyB = tagging_api.create_taxonomy(name="B", export_id="B")
+        tagging_api.set_taxonomy_orgs(taxonomyA, all_orgs=True)
+        tagging_api.set_taxonomy_orgs(taxonomyB, all_orgs=True)
+        tagging_api.add_tag_to_taxonomy(taxonomyA, "one")
+        tagging_api.add_tag_to_taxonomy(taxonomyA, "two")
+        tagging_api.add_tag_to_taxonomy(taxonomyB, "three")
+        tagging_api.add_tag_to_taxonomy(taxonomyB, "four")
+
+        # Tag the chapter
+        tagging_api.tag_object(taxonomyA, ["one", "two"], str(source_chapter.location))
+        tagging_api.tag_object(taxonomyB, ["three", "four"], str(source_chapter.location))
+
+        # Tag the child block
+        tagging_api.tag_object(taxonomyA, ["two"], str(source_block.location))
+
+        # Refresh.
+        source_chapter = self.store.get_item(source_chapter.location)
+        expected_chapter_tags = 'A:one,two;B:four,three'
+        assert source_chapter.serialize_tag_data() == expected_chapter_tags
+
+        source_block = self.store.get_item(source_block.location)
+        expected_block_tags = 'A:two'
+        assert source_block.serialize_tag_data() == expected_block_tags
+
+        # Duplicate the chapter (and its children)
+        dupe_location = duplicate_block(
+            parent_usage_key=source_course.location,
+            duplicate_source_usage_key=source_chapter.location,
+            user=user,
+        )
+        dupe_chapter = self.store.get_item(dupe_location)
+        self.assertEqual(len(dupe_chapter.get_children()), 1)
+        dupe_block = dupe_chapter.get_children()[0]
+
+        # Check that the duplicated blocks also duplicated tags
+        assert dupe_chapter.serialize_tag_data() == expected_chapter_tags
+        assert dupe_block.serialize_tag_data() == expected_block_tags
+
 
 @ddt.ddt
 class TestMoveItem(ItemTest):
diff --git a/cms/djangoapps/contentstore/views/tests/test_clipboard_paste.py b/cms/djangoapps/contentstore/views/tests/test_clipboard_paste.py
index 12f620b41e14..07c06e960f53 100644
--- a/cms/djangoapps/contentstore/views/tests/test_clipboard_paste.py
+++ b/cms/djangoapps/contentstore/views/tests/test_clipboard_paste.py
@@ -203,10 +203,8 @@ def test_copy_and_paste_unit_with_tags(self):
         # Only tags from the taxonomy that is associated with the dest org should be copied
         tags = list(tagging_api.get_object_tags(str(dest_unit_key)))
         assert len(tags) == 2
-        assert str(tags[0]) == '<ObjectTag> ' \
-            'block-v1:org.2025+course_2025+Destination_Course+type@vertical+block@vertical1: test_taxonomy=tag_1'
-        assert str(tags[1]) == '<ObjectTag> ' \
-            'block-v1:org.2025+course_2025+Destination_Course+type@vertical+block@vertical1: test_taxonomy=tag_2'
+        assert str(tags[0]) == f'<ObjectTag> {dest_unit_key}: test_taxonomy=tag_1'
+        assert str(tags[1]) == f'<ObjectTag> {dest_unit_key}: test_taxonomy=tag_2'
 
     def test_paste_with_assets(self):
         """
diff --git a/cms/lib/xblock/tagging/tagged_block_mixin.py b/cms/lib/xblock/tagging/tagged_block_mixin.py
index 5c536f480994..da2ef3c8b57f 100644
--- a/cms/lib/xblock/tagging/tagged_block_mixin.py
+++ b/cms/lib/xblock/tagging/tagged_block_mixin.py
@@ -1,4 +1,6 @@
-# lint-amnesty, pylint: disable=missing-module-docstring
+"""
+Content tagging functionality for XBlocks.
+"""
 from urllib.parse import quote, unquote
 
 
@@ -6,6 +8,17 @@ class TaggedBlockMixin:
     """
     Mixin containing XML serializing and parsing functionality for tagged blocks
     """
+    def studio_post_duplicate(self, store, source_item):
+        """
+        Duplicates content tags from the source_item.
+        """
+        if hasattr(super(), 'studio_post_duplicate'):
+            super().studio_post_duplicate()
+
+        if hasattr(source_item, 'serialize_tag_data'):
+            tags = source_item.serialize_tag_data()
+            self.xml_attributes['tags-v1'] = tags
+        self.add_tags_from_xml()
 
     def serialize_tag_data(self):
         """
diff --git a/openedx/core/djangoapps/content_tagging/api.py b/openedx/core/djangoapps/content_tagging/api.py
index ebb5c376d346..b9b7f47a7039 100644
--- a/openedx/core/djangoapps/content_tagging/api.py
+++ b/openedx/core/djangoapps/content_tagging/api.py
@@ -203,3 +203,4 @@ def set_object_tags(
 resync_object_tags = oel_tagging.resync_object_tags
 get_object_tags = oel_tagging.get_object_tags
 tag_object = oel_tagging.tag_object
+add_tag_to_taxonomy = oel_tagging.add_tag_to_taxonomy