Proteus was originally run by a group of corporate types from a number of the different megas who'd secretly embezzled the cash to help set it up and then repaid it back from the profits to help cover their tracks. When it was finally discovered the megas were a little bit annoyed and argued sucesfully, to the Corporate Court I'd assume, that since it was their money that helped found the company that they should own it. The old board members got a bullet to the back of the head and the megas they were from nominated their own people to replace them on the board.

This is from a while back so you might want one of the German board members to verrify it, but Proteus was made up of a consortium of company men from AG Chemie, Cross Applied Technologies, IFMU, Shiawase (replacing Fuchi when the corp split), Yamatetsu and Ruhrmetall.

The mention in one of the SotA books about Ares Thor shot-ing one of Proteus' arkoblocks near the Romo islands was to open the thing up to allow a runner team to get in and access the corps standalone central database to prove what they suspected. It was one of the German published adventures. Amusingly it was called Deep Blue IIRC, a double joke.