[Cyrien]

You should go after both of them. Unless Gator went to those companies and said
"Gee, we will pay you this money to have this program install with yours but you have to make sure that the user knows they are installing it and exactly what it does when it installs with yours."

I doubt that conversation occurred at all, ever. Thus both companies would be on my target list, but Gator would be on top because they produced it. I can target the other company but then Gator will just goto the next one and the next one over and over against and it keeps going. Get the source and it stops, get the symptons and you will be doing it over and over.