diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 914e315845..31fb679b4c 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -109,11 +109,12 @@ ifeq "" "$(DEFAULT_APP_TARGET_SDK)"
 endif
 
 ifeq "" "$(PLATFORM_SECURITY_PATCH)"
-  # Used to indicate the security patch that has been applied to the device.
-  # Must be of the form "YYYY-MM-DD" on production devices.
-  #
-  # If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-  PLATFORM_SECURITY_PATCH := 2016-10-05
+    #  Used to indicate the security patch that has been applied to the device.
+    #  It must signify that the build includes all security patches issued up through the designated Android Public Security Bulletin.
+    #  It must be of the form "YYYY-MM-DD" on production devices.
+    #  It must match one of the Android Security Patch Level strings of the Public Security Bulletins.
+    #  If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
+      PLATFORM_SECURITY_PATCH := 2016-10-05
 endif
 
 ifeq "" "$(PLATFORM_BASE_OS)"