diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index af7bf15500..f4a2b4e590 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -209,6 +209,7 @@ class CacheDescriptor(object):
 
         wrapped.invalidate = self.cache.invalidate
         wrapped.invalidate_all = self.cache.invalidate_all
+        wrapped.invalidate_many = self.cache.invalidate_many
         wrapped.prefill = self.cache.prefill
 
         obj.__dict__[self.orig.__name__] = wrapped