The vehicle was awarded the German patent, number 37435, for which Karl Benz applied on January 29, 1886. Following official procedures, the date of the application became the patent date for the invention once the patent was granted, which occurred in November of that year.
Although Benz's wife, Bertha, financed the development process, and would hold patent rights under modern law, as a married woman she was not allowed to apply for the patent.
Benz officially unveiled his invention to the public on July 3, 1886, on the Ringstrasse (Ringstraße) in Mannheim, Germany.
About 25 Patent Motorwagens were built between 1886 and 1893.
The major features of the two-seater vehicle, which was completed in 1885, were the compact high-speed single-cylinder four-stroke engine installed horizontally at the rear, the tubular steel frame, the differential and three wire-spoked wheels. The engine output was 0.75 hp (0.55 kW). Details included an automatic intake slide, a controlled exhaust valve, high-voltage electrical vibrator ignition with spark plug, and water/thermo siphon evaporation cooling.
On January 29, 1886, Benz applied for a patent for his “vehicle powered by a gas engine.” The patent – number 37435 – may be regarded as the birth certificate of the automobile. In July 1886 the newspapers reported on the first public outing of the three-wheeled Benz Patent Motor Car, model no. 1