diff --git a/course_discovery/apps/api/tests/test_utils.py b/course_discovery/apps/api/tests/test_utils.py
index 0cd51f8022..1cda0d83a8 100644
--- a/course_discovery/apps/api/tests/test_utils.py
+++ b/course_discovery/apps/api/tests/test_utils.py
@@ -169,7 +169,7 @@ def test_generate_data_for_studio_api_without_team(self):
         mock_logger.assert_called_with(
             'No course team admin specified for course [%s]. This may result in a Studio course run '
             'being created without a course team.',
-            run.key.split('/')[1]
+            run.key.split('+')[1]
         )
 
     def test_calculate_course_run_key_run_value_with_multiple_runs_per_trimester(self):
diff --git a/course_discovery/apps/api/v1/tests/test_views/test_catalog_queries.py b/course_discovery/apps/api/v1/tests/test_views/test_catalog_queries.py
index cfb025f9fd..f7c2c95408 100644
--- a/course_discovery/apps/api/v1/tests/test_views/test_catalog_queries.py
+++ b/course_discovery/apps/api/v1/tests/test_views/test_catalog_queries.py
@@ -13,7 +13,7 @@ def setUp(self):
         self.user = UserFactory(is_staff=True, is_superuser=True)
         self.client.force_authenticate(self.user)
         self.course = CourseFactory(partner=self.partner, key='simple_key')
-        self.course_run = CourseRunFactory(course=self.course)
+        self.course_run = CourseRunFactory(course=self.course, key='simple/key/run')
         self.url_base = reverse('api:v1:catalog-query_contains')
         self.error_message = 'CatalogQueryContains endpoint requires query and identifiers list(s)'
 
diff --git a/course_discovery/apps/api/v1/tests/test_views/test_course_runs.py b/course_discovery/apps/api/v1/tests/test_views/test_course_runs.py
index c68f500032..41e09b5a90 100644
--- a/course_discovery/apps/api/v1/tests/test_views/test_course_runs.py
+++ b/course_discovery/apps/api/v1/tests/test_views/test_course_runs.py
@@ -1,6 +1,7 @@
 import datetime
 import urllib
 from unittest import mock
+from urllib.parse import urlencode
 
 import ddt
 import pytest
@@ -1031,7 +1032,7 @@ def test_filter_by_keys(self):
         CourseRun.objects.all().delete()
         expected = CourseRunFactory.create_batch(3, course__partner=self.partner)
         keys = ','.join([course.key for course in expected])
-        url = '{root}?keys={keys}'.format(root=reverse('api:v1:course_run-list'), keys=keys)
+        url = '{root}?{params}'.format(root=reverse('api:v1:course_run-list'), params=urlencode({'keys': keys}))
         self.assert_list_results(url, expected)
 
     def test_filter_by_marketable(self):
diff --git a/course_discovery/apps/api/v1/tests/test_views/test_courses.py b/course_discovery/apps/api/v1/tests/test_views/test_courses.py
index 97ad39b106..4af715cfbe 100644
--- a/course_discovery/apps/api/v1/tests/test_views/test_courses.py
+++ b/course_discovery/apps/api/v1/tests/test_views/test_courses.py
@@ -1,5 +1,6 @@
 import datetime
 from unittest import mock
+from urllib.parse import urlencode
 
 import ddt
 import pytest
@@ -269,7 +270,7 @@ def test_list_key_filter(self):
         """ Verify the endpoint returns a list of courses filtered by the specified keys. """
         courses = CourseFactory.create_batch(3, partner=self.partner)
         keys = ','.join([course.key for course in courses])
-        url = '{root}?keys={keys}'.format(root=reverse('api:v1:course-list'), keys=keys)
+        url = '{root}?{params}'.format(root=reverse('api:v1:course-list'), params=urlencode({'keys': keys}))
 
         with self.assertNumQueries(49):
             response = self.client.get(url)
diff --git a/course_discovery/apps/course_metadata/models.py b/course_discovery/apps/course_metadata/models.py
index fe2403a421..f9bafd092b 100644
--- a/course_discovery/apps/course_metadata/models.py
+++ b/course_discovery/apps/course_metadata/models.py
@@ -21,6 +21,7 @@
 from django_extensions.db.models import TimeStampedModel
 from elasticsearch.exceptions import RequestError
 from elasticsearch_dsl.query import Q as ESDSLQ
+from opaque_keys.edx.keys import CourseKey
 from parler.models import TranslatableModel, TranslatedFieldsModel
 from simple_history.models import HistoricalRecords
 from solo.models import SingletonModel
@@ -1983,6 +1984,8 @@ def could_be_marketable(self):
         """
         if not self.type.is_marketable:
             return False
+        if CourseKey.from_string(self.key).deprecated:  # Old Mongo courses are not marketed
+            return False
         return not self.draft
 
     @property
diff --git a/course_discovery/apps/course_metadata/tests/factories.py b/course_discovery/apps/course_metadata/tests/factories.py
index c9eefca4c8..31f821895f 100644
--- a/course_discovery/apps/course_metadata/tests/factories.py
+++ b/course_discovery/apps/course_metadata/tests/factories.py
@@ -210,7 +210,7 @@ def course_run_types(self, create, extracted, **kwargs):
 
 class CourseFactory(SalesforceRecordFactory):
     uuid = factory.LazyFunction(uuid4)
-    key = FuzzyText(prefix='course-id/')
+    key = FuzzyText(prefix='course-id+')
     key_for_reruns = FuzzyText(prefix='OrgX+')
     title = FuzzyText(prefix="Test çօմɾʂҽ ")
     short_description = FuzzyText(prefix="Test çօմɾʂҽ short description")
@@ -292,7 +292,7 @@ class Meta:
 class CourseRunFactory(SalesforceRecordFactory):
     status = CourseRunStatus.Published
     uuid = factory.LazyFunction(uuid4)
-    key = FuzzyText(prefix='course-run-id/', suffix='/fake')
+    key = FuzzyText(prefix='course-v1:org+', suffix='+fake')
     external_key = None
     course = factory.SubFactory(CourseFactory)
     title_override = None
diff --git a/course_discovery/apps/course_metadata/tests/test_emails.py b/course_discovery/apps/course_metadata/tests/test_emails.py
index fd7409f548..20aad8a0b3 100644
--- a/course_discovery/apps/course_metadata/tests/test_emails.py
+++ b/course_discovery/apps/course_metadata/tests/test_emails.py
@@ -114,7 +114,7 @@ def assertEmailNotSent(self, function, reason):
                     emails.logger.name,
                     'INFO',
                     StringComparison('Not sending notification email for template course_metadata/email/.* because ' +
-                                     reason),
+                                     re.escape(reason)),
                 )
             )
 
@@ -149,22 +149,23 @@ def test_send_email_for_internal_review(self):
         restricted_url = self.partner.lms_admin_url.rstrip('/') + '/embargo/restrictedcourse/'
         self.assertEmailSent(
             emails.send_email_for_internal_review,
-            f'^Review requested: {self.course_run.key} - {self.course_run.title}$',
+            f'^Review requested: {re.escape(self.course_run.key)} - {self.course_run.title}$',
             [self.pc],
             both_regexes=[
                 'Dear %s,' % self.pc.full_name,
-                'MyOrg has submitted %s for review.' % self.course_run.key,
+                'MyOrg has submitted %s for review.' % re.escape(self.course_run.key),
             ],
             html_regexes=[
                 '<a href="%s">View this course run in Publisher</a> to review the changes and mark it as reviewed.' %
                 self.publisher_url,
-                'This is a good time to <a href="%s">review this course run in Studio</a>.' % self.studio_url,
+                'This is a good time to <a href="%s">review this course run in Studio</a>.' %
+                re.escape(self.studio_url),
                 'Visit the <a href="%s">restricted course admin page</a> to set embargo rules for this course, '
                 'as needed.' % restricted_url,
             ],
             text_regexes=[
                 '\n\nPublisher page: %s\n' % self.publisher_url,
-                '\n\nStudio page: %s\n' % self.studio_url,
+                '\n\nStudio page: %s\n' % re.escape(self.studio_url),
                 '\n\nRestricted Course admin: %s\n' % restricted_url,
             ],
         )
@@ -225,7 +226,7 @@ def test_send_email_for_go_live(self):
             **kwargs,
         )
         self.assertEmailContains(
-            subject=f'^Published: {self.course_run.key} - {self.course_run.title}$',
+            subject=f'^Published: {re.escape(self.course_run.key)} - {self.course_run.title}$',
             to_users=[self.pc],
             index=1,
             **kwargs,
diff --git a/course_discovery/apps/course_metadata/tests/test_lookups.py b/course_discovery/apps/course_metadata/tests/test_lookups.py
index 465f85c6f8..85e0138dda 100644
--- a/course_discovery/apps/course_metadata/tests/test_lookups.py
+++ b/course_discovery/apps/course_metadata/tests/test_lookups.py
@@ -1,5 +1,5 @@
 import json
-from urllib.parse import quote
+from urllib.parse import quote, urlencode
 
 import pytest
 from django.test import TestCase
@@ -17,7 +17,7 @@
 class TestAutocomplete:
     def assert_valid_query_result(self, client, path, query, expected_result):
         """ Asserts a query made against the given endpoint returns the expected result. """
-        response = client.get(path + f'?q={query}')
+        response = client.get(path + f'?{urlencode({"q": query})}')
         data = json.loads(response.content.decode('utf-8'))
         assert len(data['results']) == 1
         assert data['results'][0]['text'] == str(expected_result)
diff --git a/course_discovery/apps/course_metadata/tests/test_models.py b/course_discovery/apps/course_metadata/tests/test_models.py
index a1e645f290..5dd8ce0f32 100644
--- a/course_discovery/apps/course_metadata/tests/test_models.py
+++ b/course_discovery/apps/course_metadata/tests/test_models.py
@@ -896,6 +896,17 @@ def test_could_be_marketable(self, draft, type_is_marketable, expected):
                 course_run.save()
                 assert mock_publish_obj.called == expected
 
+    @ddt.data(
+        ('old/mongo/key', False),
+        ('course-v1:modern+style+key', True),
+    )
+    @ddt.unpack
+    def test_old_mongo_not_marketable(self, key, expected):
+        course_run = factories.CourseRunFactory.create(key=key)
+        factories.SeatFactory.create(course_run=course_run)
+        assert course_run.is_marketable == expected
+        assert course_run.could_be_marketable == expected
+
 
 class CourseRunTestsThatNeedSetUp(OAuth2Mixin, TestCase):
     """