Z:gnu-www-ja-free-digital-society--737c8f-Now, evidently, if a program i/en

Now, evidently, if a program implements a secret format, that's because the program is not free software. So this is another kind of malicious feature. Surveillance is one kind of malicious feature that you find in some nonfree programs; using secret formats to restrict the users is another kind of malicious feature that you also find in some nonfree programs.