Let me play devil's advocate here. Is there any proof that the companies who are linked to are aware of the links? Isn't it possible that someone else (say, a r

Let me play devil's advocate here. Is there any proof that the companies who are linked to are aware of the links? Isn't it possible that someone else (say, a rival company looking to tarnish a rival's reputation) is buying the links? Or that the companies have contracted out SEO to a third party, which is buying links in violation of their contract?