Use of third party logos

"Aah, I see you're coming from Google"

[DrDoc]

Time and time again I visit a page telling me something like "aah, I see you're coming from Google"... displaying the word "Google" using a miniature version of their logo.

Now, I wonder... is it really ok to do that? Or, could Google sue them for copyright infringment and/or use of trademark without permission?

[rogerd]

Here's Google's explanation about use of their logo: When Do I Need Permission to Use Google Brand Features? [google.com]

They do indicate that you don't need a permission if you are adding a Google search link.

Each company will have its own rules on proper use of its logo.

[DrDoc]

But then you also have pages like:
[google.com...]
[google.com...]

So I guess it depends on how you plan on using it.

AltaVista says that you can use their logo for non-commercial purposes (http://www.altavista.com/web/legal/termsofuse [altavista.com]) ...non-commercial purposes, but that doesn't necessarily mean that the page itself is non-commercial.

Yahoo! seems to be the strictest one: [docs.yahoo.com...]

[rogerd]

Assuming your use is in no way confusing and doesn't misrepresent your relation (none) to the SE, odds are the worst that could happen is that they would ask you to remove the logo.

If you aren't completely risk averse, you could just do it and not worry about it. (This isn't legal advice, of course.) Or, make them links to the SE and you'll be on even more solid footing.