diff --git a/ruby/ext/google/protobuf_c/protobuf.c b/ruby/ext/google/protobuf_c/protobuf.c
index c15a1caa6c..ad6239ee3f 100644
--- a/ruby/ext/google/protobuf_c/protobuf.c
+++ b/ruby/ext/google/protobuf_c/protobuf.c
@@ -241,16 +241,17 @@ static void ObjectCache_Init(VALUE protobuf) {
   item_try_add = rb_intern("try_add");
 
   rb_gc_register_address(&weak_obj_cache);
+  VALUE internal = rb_const_get(protobuf, rb_intern("Internal"));
 #if SIZEOF_LONG >= SIZEOF_VALUE
-  VALUE cache_class = rb_const_get(protobuf, rb_intern("ObjectCache"));
+  VALUE cache_class = rb_const_get(internal, rb_intern("ObjectCache"));
 #else
-  VALUE cache_class = rb_const_get(protobuf, rb_intern("LegacyObjectCache"));
+  VALUE cache_class = rb_const_get(internal, rb_intern("LegacyObjectCache"));
 #endif
 
   weak_obj_cache = rb_class_new_instance(0, NULL, cache_class);
-  rb_const_set(protobuf, rb_intern("OBJECT_CACHE"), weak_obj_cache);
-  rb_const_set(protobuf, rb_intern("SIZEOF_LONG"), INT2NUM(SIZEOF_LONG));
-  rb_const_set(protobuf, rb_intern("SIZEOF_VALUE"), INT2NUM(SIZEOF_VALUE));
+  rb_const_set(internal, rb_intern("OBJECT_CACHE"), weak_obj_cache);
+  rb_const_set(internal, rb_intern("SIZEOF_LONG"), INT2NUM(SIZEOF_LONG));
+  rb_const_set(internal, rb_intern("SIZEOF_VALUE"), INT2NUM(SIZEOF_VALUE));
 }
 
 static VALUE ObjectCache_GetKey(const void *key) {
diff --git a/ruby/lib/google/protobuf.rb b/ruby/lib/google/protobuf.rb
index 20570a08df..fdfa9b687e 100644
--- a/ruby/lib/google/protobuf.rb
+++ b/ruby/lib/google/protobuf.rb
@@ -7,7 +7,7 @@
 
 # require mixins before we hook them into the java & c code
 require 'google/protobuf/message_exts'
-require 'google/protobuf/object_cache'
+require 'google/protobuf/internal/object_cache'
 
 # We define these before requiring the platform-specific modules.
 # That way the module init can grab references to these.
diff --git a/ruby/lib/google/protobuf/ffi/object_cache.rb b/ruby/lib/google/protobuf/ffi/object_cache.rb
index ff287115a0..61f5c8e7f4 100644
--- a/ruby/lib/google/protobuf/ffi/object_cache.rb
+++ b/ruby/lib/google/protobuf/ffi/object_cache.rb
@@ -18,13 +18,13 @@ module Google
 
     def self.cache_implementation
       if interpreter_supports_non_finalized_keys_in_weak_map? and SIZEOF_LONG >= SIZEOF_VALUE
-        Google::Protobuf::ObjectCache
+        Google::Protobuf::Internal::ObjectCache
       else
-        Google::Protobuf::LegacyObjectCache
+        Google::Protobuf::Internal::LegacyObjectCache
       end
     end
 
     public
     OBJECT_CACHE = cache_implementation.new
   end
-end
\ No newline at end of file
+end
diff --git a/ruby/lib/google/protobuf/internal/object_cache.rb b/ruby/lib/google/protobuf/internal/object_cache.rb
new file mode 100644
index 0000000000..38e9bb5fe9
--- /dev/null
+++ b/ruby/lib/google/protobuf/internal/object_cache.rb
@@ -0,0 +1,99 @@
+# Protocol Buffers - Google's data interchange format
+# Copyright 2023 Google Inc.  All rights reserved.
+#
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+module Google
+  module Protobuf
+    module Internal
+      # A pointer -> Ruby Object cache that keeps references to Ruby wrapper
+      # objects.  This allows us to look up any Ruby wrapper object by the address
+      # of the object it is wrapping. That way we can avoid ever creating two
+      # different wrapper objects for the same C object, which saves memory and
+      # preserves object identity.
+      #
+      # We use WeakMap for the cache. If sizeof(long) > sizeof(VALUE), we also
+      # need a secondary Hash to store WeakMap keys, because our pointer keys may
+      # need to be stored as Bignum instead of Fixnum.  Since WeakMap is weak for
+      # both keys and values, a Bignum key will cause the WeakMap entry to be
+      # collected immediately unless there is another reference to the Bignum.
+      # This happens on 64-bit Windows, on which pointers are 64 bits but longs
+      # are 32 bits. In this case, we enable the secondary Hash to hold the keys
+      # and prevent them from being collected.
+      class ObjectCache
+        def initialize
+          @map = ObjectSpace::WeakMap.new
+          @mutex = Mutex.new
+        end
+
+        def get(key)
+          @map[key]
+        end
+
+        def try_add(key, value)
+          @map[key] || @mutex.synchronize do
+            @map[key] ||= value
+          end
+        end
+      end
+
+      class LegacyObjectCache
+        def initialize
+          @secondary_map = {}
+          @map = ObjectSpace::WeakMap.new
+          @mutex = Mutex.new
+        end
+
+        def get(key)
+          value = if secondary_key = @secondary_map[key]
+            @map[secondary_key]
+          else
+            @mutex.synchronize do
+              @map[(@secondary_map[key] ||= Object.new)]
+            end
+          end
+
+          # GC if we could remove at least 2000 entries or 20% of the table size
+          # (whichever is greater).  Since the cost of the GC pass is O(N), we
+          # want to make sure that we condition this on overall table size, to
+          # avoid O(N^2) CPU costs.
+          cutoff = (@secondary_map.size * 0.2).ceil
+          cutoff = 2_000 if cutoff < 2_000
+          if (@secondary_map.size - @map.size) > cutoff
+            purge
+          end
+
+          value
+        end
+
+        def try_add(key, value)
+          if secondary_key = @secondary_map[key]
+            if old_value = @map[secondary_key]
+              return old_value
+            end
+          end
+
+          @mutex.synchronize do
+            secondary_key ||= (@secondary_map[key] ||= Object.new)
+            @map[secondary_key] ||= value
+          end
+        end
+
+        private
+
+        def purge
+          @mutex.synchronize do
+            @secondary_map.each do |key, secondary_key|
+              unless @map.key?(secondary_key)
+                @secondary_map.delete(key)
+              end
+            end
+          end
+          nil
+        end
+      end
+    end
+  end
+end
diff --git a/ruby/lib/google/protobuf/object_cache.rb b/ruby/lib/google/protobuf/object_cache.rb
deleted file mode 100644
index d99b2a74be..0000000000
--- a/ruby/lib/google/protobuf/object_cache.rb
+++ /dev/null
@@ -1,97 +0,0 @@
-# Protocol Buffers - Google's data interchange format
-# Copyright 2023 Google Inc.  All rights reserved.
-#
-# Use of this source code is governed by a BSD-style
-# license that can be found in the LICENSE file or at
-# https://developers.google.com/open-source/licenses/bsd
-
-module Google
-  module Protobuf
-    # A pointer -> Ruby Object cache that keeps references to Ruby wrapper
-    # objects.  This allows us to look up any Ruby wrapper object by the address
-    # of the object it is wrapping. That way we can avoid ever creating two
-    # different wrapper objects for the same C object, which saves memory and
-    # preserves object identity.
-    #
-    # We use WeakMap for the cache. If sizeof(long) > sizeof(VALUE), we also
-    # need a secondary Hash to store WeakMap keys, because our pointer keys may
-    # need to be stored as Bignum instead of Fixnum.  Since WeakMap is weak for
-    # both keys and values, a Bignum key will cause the WeakMap entry to be
-    # collected immediately unless there is another reference to the Bignum.
-    # This happens on 64-bit Windows, on which pointers are 64 bits but longs
-    # are 32 bits. In this case, we enable the secondary Hash to hold the keys
-    # and prevent them from being collected.
-    class ObjectCache
-      def initialize
-        @map = ObjectSpace::WeakMap.new
-        @mutex = Mutex.new
-      end
-
-      def get(key)
-        @map[key]
-      end
-
-      def try_add(key, value)
-        @map[key] || @mutex.synchronize do
-          @map[key] ||= value
-        end
-      end
-    end
-
-    class LegacyObjectCache
-      def initialize
-        @secondary_map = {}
-        @map = ObjectSpace::WeakMap.new
-        @mutex = Mutex.new
-      end
-
-      def get(key)
-        value = if secondary_key = @secondary_map[key]
-          @map[secondary_key]
-        else
-          @mutex.synchronize do
-            @map[(@secondary_map[key] ||= Object.new)]
-          end
-        end
-
-        # GC if we could remove at least 2000 entries or 20% of the table size
-        # (whichever is greater).  Since the cost of the GC pass is O(N), we
-        # want to make sure that we condition this on overall table size, to
-        # avoid O(N^2) CPU costs.
-        cutoff = (@secondary_map.size * 0.2).ceil
-        cutoff = 2_000 if cutoff < 2_000
-        if (@secondary_map.size - @map.size) > cutoff
-          purge
-        end
-
-        value
-      end
-
-      def try_add(key, value)
-        if secondary_key = @secondary_map[key]
-          if old_value = @map[secondary_key]
-            return old_value
-          end
-        end
-
-        @mutex.synchronize do
-          secondary_key ||= (@secondary_map[key] ||= Object.new)
-          @map[secondary_key] ||= value
-        end
-      end
-
-      private
-
-      def purge
-        @mutex.synchronize do
-          @secondary_map.each do |key, secondary_key|
-            unless @map.key?(secondary_key)
-              @secondary_map.delete(key)
-            end
-          end
-        end
-        nil
-      end
-    end
-  end
-end
diff --git a/ruby/tests/object_cache_test.rb b/ruby/tests/object_cache_test.rb
index 1d9b77f9e7..1125e9e88b 100644
--- a/ruby/tests/object_cache_test.rb
+++ b/ruby/tests/object_cache_test.rb
@@ -3,11 +3,11 @@ require 'test/unit'
 
 class PlatformTest < Test::Unit::TestCase
   def test_correct_implementation_for_platform
-    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::OBJECT_CACHE
-    if Google::Protobuf::SIZEOF_LONG >= Google::Protobuf::SIZEOF_VALUE and not defined? JRUBY_VERSION
-      assert_instance_of Google::Protobuf::ObjectCache, Google::Protobuf::OBJECT_CACHE
+    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::Internal::OBJECT_CACHE
+    if Google::Protobuf::Internal::SIZEOF_LONG >= Google::Protobuf::Internal::SIZEOF_VALUE and not defined? JRUBY_VERSION
+      assert_instance_of Google::Protobuf::Internal::ObjectCache, Google::Protobuf::Internal::OBJECT_CACHE
     else
-      assert_instance_of Google::Protobuf::LegacyObjectCache, Google::Protobuf::OBJECT_CACHE
+      assert_instance_of Google::Protobuf::Internal::LegacyObjectCache, Google::Protobuf::Internal::OBJECT_CACHE
     end
   end
 end
@@ -47,8 +47,8 @@ end
 
 class ObjectCacheTest < Test::Unit::TestCase
   def create
-    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::OBJECT_CACHE
-    Google::Protobuf::ObjectCache.new
+    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::Internal::OBJECT_CACHE
+    Google::Protobuf::Internal::ObjectCache.new
   end
 
   include ObjectCacheTestModule
@@ -56,10 +56,9 @@ end
 
 class LegacyObjectCacheTest < Test::Unit::TestCase
   def create
-    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::OBJECT_CACHE
-    Google::Protobuf::LegacyObjectCache.new
+    omit('OBJECT_CACHE not defined') unless defined? Google::Protobuf::Internal::OBJECT_CACHE
+    Google::Protobuf::Internal::LegacyObjectCache.new
   end
 
   include ObjectCacheTestModule
 end
-