Routers MUST support the Record Route option in forwarded packets.
A router MAY provide a configuration option that, if enabled, will cause the router to ignore (i.e., pass through unchanged) Record Route options in forwarded packets. If provided, such an option MUST default to enabling the record-route. This option should not affect the processing of Record Route options in datagrams received by the router itself (in particular, Record Route options in ICMP echo requests will still be processed according to Section [4.3.3.6]).
There are some people who believe that Record Route is a security problem because it discloses information about the topology of the network. Thus, this document allows it to be disabled.