Like photos, sales copy, order buttons, etc., chances are your logo will either be ripped off by someone or you’ll get a claim one day that you stole someone else’s logo.
Copying it is one thing. The gray area is where substantive changes have been made. On the funny side, Dogbert in the Dilbert comic strip designed a logo that supposedly was the “circle of quality”…which happened to look like the stain your coffee mug would make if placed on a sheet of white paper. A couple years later, Lucent came out with a logo that looked like the coffee mug stain. Wonder if the designer reads Dilbert.
For an interesting review of the logo theft issue, check out two related posts at the LogoBlog.org.