Are there different types of watermarking, and do they require different types of security?

I can identify two types of watermarking. One is what I call "branding." That is, you put "watermarks" on your documents to identify them as yours, before sending them out over the "net." These watermarks are usually invisible, but perhaps they need not be, if all they do is to act as your "signature."

Another type of watermark might be a data transmitter. That is, it will record times that the record itself changed hands from one computer to another, or when the record was altered, and this information will be sent to an address offline. I would guess that these watermarks should not be exposed.

Are these two fundamentally different applications of watermarking, and if so, how would they differ in terms of desirable/required security?