diff --git a/security/secureclock/aidl/android/hardware/security/secureclock/TimeStampToken.aidl b/security/secureclock/aidl/android/hardware/security/secureclock/TimeStampToken.aidl
index 2fbd29a..fcf2ee8 100644
--- a/security/secureclock/aidl/android/hardware/security/secureclock/TimeStampToken.aidl
+++ b/security/secureclock/aidl/android/hardware/security/secureclock/TimeStampToken.aidl
@@ -39,7 +39,7 @@
      * 32-byte HMAC-SHA256 of the above values, computed as:
      *
      *    HMAC(H,
-     *         ISecureClock.TIME_STAMP_MAC_LABEL || challenge || timestamp || securityLevel )
+     *         ISecureClock.TIME_STAMP_MAC_LABEL || challenge || timestamp || 1 )
      *
      * where:
      *
@@ -50,9 +50,7 @@
      *   ``||'' represents concatenation
      *
      * The representation of challenge and timestamp is as 64-bit unsigned integers in big-endian
-     * order. SecurityLevel is represented as a 32-bit unsigned integer in big-endian order as
-     * described in android.hardware.security.keymint.SecurityLevel. It represents the security
-     * level of the secure clock environment.
+     * order.  1, above, is a 32-bit unsigned integer, also big-endian.
      */
     byte[] mac;
 }