Regarding UN-ICAO rules for passports or other travel documents:
(1) A date of birth is optional. Date of birth can be left blank or omitted.
(2) The "name" or "identifier" does not have to have 'two parts' (i.e. surname, given name(s)) and can be a singularity JOHN or ROY or can be a singularity such as JOHN SMITH or SMITH JOHN. (as compared to SMITH, JOHN --two parts renders with a << for the separator in the MRZ).
(3) Nationality is not mandatory. 'XXX' is the standardized code for unknown or unspecified nationality such as being a national of a non-ISO-standard country.
(4) Gender.
(5) Place of birth is not mandatory (some States might require it)
Just FYI. Although "ICAO States" may make their own rules or suggestions, the UN-ICAO doesn't mandate any of the above.