Their invention was granted a patent under on August 11, 1942 (filed using her married name Hedy Kiesler Markey). However, it was technologically difficult to implement, and at the time the US Navy was not receptive to considering inventions coming from outside the military. Nevertheless, it was classified in the "red hot" category. It was first adapted in 1957 to develop a sonobuoy before the expiration of the patent, although this was denied by the Navy. At the time of the Cuban Missile Crisis in 1962, an updated version of their design was installed on Navy ships. Today, various spread-spectrum techniques are incorporated into Bluetooth technology and are similar to methods used in legacy versions of Wi-Fi. Lamarr and Antheil's contributions were formally recognized in the late twentieth and early twenty-first centuries.