diff --git a/include/hardware/keymaster_defs.h b/include/hardware/keymaster_defs.h
index f2deb72..5d29a24 100644
--- a/include/hardware/keymaster_defs.h
+++ b/include/hardware/keymaster_defs.h
@@ -330,6 +330,7 @@
     KM_PURPOSE_VERIFY = 3,     /* Usable with RSA, EC and HMAC keys. */
     KM_PURPOSE_DERIVE_KEY = 4, /* Usable with EC keys. */
     KM_PURPOSE_WRAP = 5,       /* Usable with wrapped keys. */
+    KM_PURPOSE_AGREE_KEY = 6,  /* Usable with EC keys. */
 
 } keymaster_purpose_t;