As matriculees of a degree program
(or even just as enrollers of a class)
students enter into a contract with the school.
As GRA employees, another level is added to that.
I would be surprised if an employee, as a function
of their job, developed code on an employer's equipment,
and it were NOT considered "property of the employer."
That employer-employee relationship is clearly transitive,
and has been in the past. So, if you're entering into
a contract with a Univ, and they entered into a contract
with the US Govt, then they have reasonably transferred their
rights of ownership to the US Govt.
Signing a patent agreement isn't necessarily required
for any of this to take effect. Cashing a check is sufficient.
Why is this surprising?