> - Sue them, aggressively.
On what grounds?
> - Looks for exploits in their own systems and publish their code, making it worthless.
Are you saying Google should publish exploits of Variston's systems? There's kind of a "two wrongs" problem there; such information would likely require illegal hacking ("accessing a computer system without permission") to discover.
> - Publish lists of their owners and employees
I'm sure they do as much as they can in that regard, but I'm sure such companies do much to hide their ownership and employees, and at any rate it could be seen as encouraging illegal harassment of said employees.
> ban them from Google/Microsoft services.
To the extent possible I'm sure they do this, but Google can't really stop someone from using Chrome, or always reliably detect when someone representing a malicious company is using their services.