diff --git a/library/x509_crt.c b/library/x509_crt.c
index e9672e4dd..b5ad86715 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1295,7 +1295,7 @@ static int x509_crt_parse_frame( unsigned char *start,
     p += len;
     frame->pubkey_raw.len = p - frame->pubkey_raw.p;
 
-    if( frame->version == 2 || frame->version == 3 )
+    if( frame->version != 1 )
     {
         /*
          *  issuerUniqueID  [1]  IMPLICIT UniqueIdentifier OPTIONAL,