Lockheed, Boeing et al own every trademark, patent, etc available for models they create. The governmnet or whoever tells them :this what we would like in the plane" and they go and make a model. If it's not up to specs they do it again. 

Although tax money is used, even the government can not turn around and sell the plane or model of it.  They own the plane created with THEIR specs not the actual prototype

In a world filled with causes for worry and anxiety...
we need the peace of God standing guard over our hearts and minds.
 
Jerry McCant