diff --git pepper_flash.cc pepper_flash.cc
index b21d4d1..11fac76 100644
--- pepper_flash.cc
+++ pepper_flash.cc
@@ -117,6 +117,14 @@ bool CheckPepperFlashManifest(const base::DictionaryValue& manifest,
   if (os != kPepperFlashOperatingSystem)
     return false;
 
+#if defined(OS_MACOSX)
+  // On Mac newer versions of the plugin are a universal binary and use "mac"
+  // as the value.
+  std::string arch;
+  manifest.GetStringASCII("x-ppapi-arch", &arch);
+  if (arch != kPepperFlashArch && arch != kPepperFlashOperatingSystem)
+    return false;
+#else
 // On Win64, PepperFlash manifests have "ia32" instead of "x64" so skip the
 // architecture check. TODO(wfh): remove this when crbug.com/458894 is fixed.
 #if !defined(OS_WIN) || !defined(ARCH_CPU_X86_64)
@@ -125,6 +133,7 @@ bool CheckPepperFlashManifest(const base::DictionaryValue& manifest,
   if (arch != kPepperFlashArch)
     return false;
 #endif
+#endif
 
   *version_out = version;
   return true;