One of Öller's trainees was Lars Magnus Ericsson, who was sent abroad to learn the latest technology in telegraph instrument manufacturing.  In 1876, Ericsson returned to Sweden after three years of studies and job training in Germany and Switzerland. Feeling ready to start a company of his own,  he borrowed USD 100 to use as working capital. On April 1, 1876, he established an electromechanical workshop in a kitchen he rented at Drottninggatan 15 in Stockholm, repairing telegraph instruments before going on to manufacture his own telephone and telegraph equipment as LM Ericsson & Co.

Two other Öller employees also left Öller & Company in 1878 to form their own company called Lindholm and Wikstrom. They eventually bought the Öller company from his widow when Öller died in 1889 and ran it till 1905 when the pair split up. Lindhölm left to form a new company under his own name with Wikström continuing on as before. In 1923 Lindhölm sold his firm to Albert Löfgren who was a former Öller employee as well. Both the separate Lindhölm and the Wikström companies still exist today.

The dimensions and design of Ericsson keys,  Öller keys, and Lindhölm and Wikström keys are nearly identical. The main differences in design are the connection screw placement, the hinge design, rear connection block and the wiring cut outs.

** special thanks to Ericsson Contact magazine, Neal McEwen & his  THE TELEGRAPH OFFICE  Jan Möller, Kåre Wallman, Ove Svensson  & The Swedish TELEMUSEUM   for the vast portion of this information.