How do I make a structure nonsellable?

[Fyrstar 0]

I have created a nuclear silo in the middle of the map, set to Indestructible/nonsellable with a neutral player.

 

After this structure is captured, it becomes both destructible AND sellable.

 

How do I fix this?

[nick55555 0]

I don't know. It should work.

[M0dZ0R 0]

im not quite sure on the map one, but i do know how to make a building unsellable, but the building itself, compleatly...