diff --git a/nmap.cc b/nmap.cc
index b98fad2df..3921e2cb8 100644
--- a/nmap.cc
+++ b/nmap.cc
@@ -387,8 +387,8 @@ static int ip_is_reserved(struct in_addr *ip)
   if (i1 == 172 && i2 >= 16 && i2 <= 31)
     return 1;
 
-  /* 173-185/8 is IANA reserved */
-  if (i1 >= 173 && i1 <= 185)
+  /* 175-185/8 is IANA reserved */
+  if (i1 >= 175 && i1 <= 185)
     return 1;
 
   /* 192.168.0.0/16 is reserved for private nets by RFC1819 */