>Basically, they were so worried about secrecy of their trading algorithms and people sharing them with other companies, they didn't even let people share internally for fear that one person would learn too much about their business.

That's probably actually required though.

There's a book called 73 Rules of Spycraft by Allens Dulles and these are obviously relevant for financial trading:

Rule 2, 3 and 4, are I think, the relevant ones in this case. Especially 4:

>No matter how brilliant a given individual, no matter how great his goodwill, if he is lacking in security, he will eventually prove more of a liability than asset.