It's about a passport field than can represent anything the issuing country wishes. So for example a traveller that has the value of this field changed accordin

It's about a passport field than can represent anything the issuing country wishes. So for example a traveller that has the value of this field changed according to a German law [0] to anything different than M or F (most probably other values will be represented with an X) will be denied entry to the US. https://de.wikipedia.org/wiki/Gesetz_%C3%BCber_die_Selbstbestimmung_in_Bezug_auf_den_Geschlechtseintrag https://de.wikipedia.org/wiki/Gesetz_%C3%BCber_die_Selbstbes...