diff --git a/include/openssl/x509.h b/include/openssl/x509.h
index 7bf4923..252946f 100644
--- a/include/openssl/x509.h
+++ b/include/openssl/x509.h
@@ -1203,5 +1203,6 @@
 #define X509_R_NAME_TOO_LONG 135
 #define X509_R_INVALID_PARAMETER 136
 #define X509_R_SIGNATURE_ALGORITHM_MISMATCH 137
+#define X509_R_DELTA_CRL_WITHOUT_CRL_NUMBER 138
 
 #endif