Though he was able to help several members of his family escape Austria, he was subject to internment by the British as an enemy alien after the onset of World War II. After being released in 1941 and a short spell in the Pioneer Corps, he was able to engage Henderson and Spalding, a lithography company in Camberwell run by Harold Vezey-Strong, to invest in his printed circuit idea via a specially created subsidiary of Henderson and Spalding called Technograph, but forfeited rights to his invention when he neglected to read the contract before signing it. It was a pretty standard employment contract in that he agreed to submit any patent right during his employment for a nominal fee (one pound sterling) but it also gave him 16.5 percent ownership of Technograph. It drew no interest until the United States incorporated the technology into work on the proximity fuze which was vital to counter the German V-1 flying bomb. However, he did manage to obtain his first three printed circuit patent for a wide range of applications. They were split out from a single application submitted in 1943 and finally published after long legal procedures on 21 June 1950.