László József Bíró (Hungarian pronunciation: [ˈlaːsloː ˈjoːʒɛf ˈbiːroː]; né Schweiger; 29 September 1899 – 24 October 1985), Hispanicized as Ladislao José Biro, was a Hungarian-Argentine inventor who patented the first commercially successful modern ballpoint pen.

Bíró was born to a Hungarian Jewish family in Budapest, Kingdom of Hungary, within the Austro-Hungarian Empire,[1] in 1899 to Mózes Mátyás Schweiger and Janka Ullmann.

This new design was supposedly licensed for production in the United Kingdom for supply to Royal Air Force aircrew.

Because the Reynolds workaround depended on a gravity feed, it did not infringe, but required thinner ink and a larger barrel.

[5] A ballpoint pen is widely referred to as a "biro" in many countries, including the UK, Ireland, Australia and Italy.