It is believed that wrist watch alarms were first produced in the early 1900s by Eterna. The interesting thing is that they did not actually develop the design – it was merely licensed from the German patent holders, The Durrenstein brothers. Their idea was patented in 1899, under Swiss patent # 17,104. Eterna did eventually patent an update to the original alarm watch design, # 42,203, but it is erroneously described as an actual alarm mechanism patent. To learn more about all this, be sure to check out the video below.