diff --git a/README.md b/README.md
index 68f0e7d..48259fa 100644
--- a/README.md
+++ b/README.md
@@ -37,6 +37,7 @@ encoded private key for RSA and ECDSA. In case of a private key with passphrase
 * `subject`
 * `noTimestamp`
 * `header`
+* `keyid`
 
 If `payload` is not a buffer or a string, it will be coerced into a string using `JSON.stringify`.