I read that the successors were taken over by Eduard Kettner in 1912 but I've seen an ad with the Clever name that was supposedly from 1914. I hope that clears things up. Axel says that F. Jaeger was not particularly diligent in defending the "Rekord" patent and it was often copied. Maybe he wasn't diligent in defending his trade mark either.
Franz Jäger's adverts give that his was a 10 point lockup and he lists his sales outlets in this 1907/1908 advert and Engelbert Clever is listed as having a successor.
But a a similar period article on the Verschluß der Rekordgewehr gives that it has a 20(friction surfaces) point lockup and is manufactured in Liege by Scholberg & Delheid
and adverts for it thru Thieme & Schlegelmilch and those of Franz Jäger are either found on adjacent pages or possibly on the same page.
With Engelbert Clever's successor being a sales outlet for Franz Jäger and having Belgian proofs I wonder if Franz Jäger didn't source the work to Liege or have some business relationship with Scholberg & Delheid