I suspect there are several very big miners who have been backed by serious money who have built and operate their own chips and tell no-one.
These entities have a name for it. It is called 國營企業.
State-owned enterprises?
Who else will have that kind of resource?
Put your tinfoil hat on, I never understood why ASICMINER never said anything official about Gen 2, and then we find out it was canceled because it was "unsatisfactory".