seem like the Go rule which the players need to own the space around the opponent space, the players can force the opponent to sell the business in the half price of the productivity whatever the industry is.
The Combo system, if the players can own all the space in the same color the players will get plus the productivity for each by the number of city that they own on that space color, for example the player own Saarland and Rheinland that are all of the sky blue color the productivity of these 2 spaces will increase 2 for each space.