DaStarBuG, that's exactly what it means. And there is some sense to that. Although legally, there has to be some limitation to that. It can't go on forever.
For example, if the company's ads don't appear on one's site for a certain stated period of time, then the prohibition can't be enforced (although Google might not agree and then it's a question for the courts).
In my youth I worked for a office temp company. They had a similar policy where any company who used your services through an office temp agency can't then hire you directly for a period of six months without a penalty being paid to the temp agency. I see it being the same thing with Adsense, although I was looking for a time limitation from Google.
If the company goes away for a year, then comes back to me with an offer, would I then be able to make a deal with them without incurring a violation from Google? I'm not about to violate the policy, but I'd like to see what the time limit is.