diff -up cups-1.6.3/cups/util.c.download-ppd cups-1.6.3/cups/util.c
--- cups-1.6.3/cups/util.c.download-ppd	2020-02-11 13:36:26.923903558 +0100
+++ cups-1.6.3/cups/util.c	2020-02-11 13:38:25.473972412 +0100
@@ -1712,10 +1712,9 @@ cups_get_printer_uri(
       device_uri = attr->values[0].string.text;
 
     if (device_uri &&
-        (!strncmp(device_uri, "ipp://", 6) ||
-         !strncmp(device_uri, "ipps://", 7) ||
-         ((strstr(device_uri, "._ipp.") != NULL ||
-           strstr(device_uri, "._ipps.") != NULL) &&
+        (((!strncmp(device_uri, "ipp://", 6) || !strncmp(device_uri, "ipps://", 7)) &&
+	  (strstr(device_uri, "/printers/") != NULL || strstr(device_uri, "/classes/") != NULL)) ||
+         ((strstr(device_uri, "._ipp.") != NULL || strstr(device_uri, "._ipps.") != NULL) &&
           !strcmp(device_uri + strlen(device_uri) - 5, "/cups"))))
     {
      /*