[giancarlostoro]

You're saying nobody would be able to test if, when and what an Antivirus program is sending over the internet? If it all of a sudden is uploading enough data over to some server vs downloading (for updates) it's kind of a tall tale sign that it's phoning home with files. I don't use AV software anymore since I'm mostly on Linux, if I'm on Windows it's dedicated to Windows based programming, all my browsing is isolated usually.

You can go as far as finding the amount of data software is sending over the wire through the Task Manager -> Performance -> Resource Monitor. And to say an AntiVirus can hide this would mean it shouldn't be trusted whatsoever if it behaves like malware. The type of reputation any sane A/V company does not want to fall under.