diff --git a/django/contrib/contenttypes/models.py b/django/contrib/contenttypes/models.py
index a0c9fb0903a..6a212ab684f 100644
--- a/django/contrib/contenttypes/models.py
+++ b/django/contrib/contenttypes/models.py
@@ -10,13 +10,15 @@ from django.utils.translation import ugettext_lazy as _
 class ContentTypeManager(models.Manager):
     use_in_migrations = True
 
-    # Cache to avoid re-looking up ContentType objects all over the place.
-    # This cache is shared by all the get_for_* methods.
-    _cache = {}
+    def __init__(self, *args, **kwargs):
+        super(ContentTypeManager, self).__init__(*args, **kwargs)
+        # Cache shared by all the get_for_* methods to speed up
+        # ContentType retrieval.
+        self._cache = {}
 
     def get_by_natural_key(self, app_label, model):
         try:
-            ct = self.__class__._cache[self.db][(app_label, model)]
+            ct = self._cache[self.db][(app_label, model)]
         except KeyError:
             ct = self.get(app_label=app_label, model=model)
             self._add_to_cache(self.db, ct)
@@ -31,7 +33,7 @@ class ContentTypeManager(models.Manager):
 
     def _get_from_cache(self, opts):
         key = (opts.app_label, opts.model_name)
-        return self.__class__._cache[self.db][key]
+        return self._cache[self.db][key]
 
     def get_for_model(self, model, for_concrete_model=True):
         """
@@ -118,7 +120,7 @@ class ContentTypeManager(models.Manager):
         (though ContentTypes are obviously not created on-the-fly by get_by_id).
         """
         try:
-            ct = self.__class__._cache[self.db][id]
+            ct = self._cache[self.db][id]
         except KeyError:
             # This could raise a DoesNotExist; that's correct behavior and will
             # make sure that only correct ctypes get stored in the cache dict.
@@ -133,15 +135,15 @@ class ContentTypeManager(models.Manager):
         django.contrib.contenttypes.management.update_contenttypes for where
         this gets called).
         """
-        self.__class__._cache.clear()
+        self._cache.clear()
 
     def _add_to_cache(self, using, ct):
         """Insert a ContentType into the cache."""
         # Note it's possible for ContentType objects to be stale; model_class() will return None.
         # Hence, there is no reliance on model._meta.app_label here, just using the model fields instead.
         key = (ct.app_label, ct.model)
-        self.__class__._cache.setdefault(using, {})[key] = ct
-        self.__class__._cache.setdefault(using, {})[ct.id] = ct
+        self._cache.setdefault(using, {})[key] = ct
+        self._cache.setdefault(using, {})[ct.id] = ct
 
 
 @python_2_unicode_compatible
diff --git a/docs/releases/1.8.10.txt b/docs/releases/1.8.10.txt
index c9fbd0470d7..b1319ff8020 100644
--- a/docs/releases/1.8.10.txt
+++ b/docs/releases/1.8.10.txt
@@ -26,3 +26,6 @@ Bugfixes
   ``URLValidator`` to fix a regression in Django 1.8 (:ticket:`26204`).
 
 * Fixed ``BoundField`` to reallow slices of subwidgets (:ticket:`26267`).
+
+* Prevented ``ContentTypeManager`` instances from sharing their cache
+  (:ticket:`26286`).
diff --git a/docs/releases/1.9.3.txt b/docs/releases/1.9.3.txt
index 625899daa02..e0447d2afef 100644
--- a/docs/releases/1.9.3.txt
+++ b/docs/releases/1.9.3.txt
@@ -49,3 +49,6 @@ Bugfixes
 
 * Fixed a crash when passing a nonexistent template name to the cached template
   loader's ``load_template()`` method (:ticket:`26280`).
+
+* Prevented ``ContentTypeManager`` instances from sharing their cache
+  (:ticket:`26286`).
diff --git a/tests/contenttypes_tests/test_models.py b/tests/contenttypes_tests/test_models.py
index 12010ac7819..7644a8ea302 100644
--- a/tests/contenttypes_tests/test_models.py
+++ b/tests/contenttypes_tests/test_models.py
@@ -1,6 +1,6 @@
 from __future__ import unicode_literals
 
-from django.contrib.contenttypes.models import ContentType
+from django.contrib.contenttypes.models import ContentType, ContentTypeManager
 from django.contrib.contenttypes.views import shortcut
 from django.contrib.sites.shortcuts import get_current_site
 from django.db.utils import IntegrityError, OperationalError, ProgrammingError
@@ -168,6 +168,18 @@ class ContentTypesTests(TestCase):
             DeferredProxyModel: proxy_model_ct,
         })
 
+    def test_cache_not_shared_between_managers(self):
+        with self.assertNumQueries(1):
+            ContentType.objects.get_for_model(ContentType)
+        with self.assertNumQueries(0):
+            ContentType.objects.get_for_model(ContentType)
+        other_manager = ContentTypeManager()
+        other_manager.model = ContentType
+        with self.assertNumQueries(1):
+            other_manager.get_for_model(ContentType)
+        with self.assertNumQueries(0):
+            other_manager.get_for_model(ContentType)
+
     @override_settings(ALLOWED_HOSTS=['example.com'])
     def test_shortcut_view(self):
         """