Rand Fishkin from Moz posted on Google+ that Google AdWords seems to have lifted their ban on link selling/buying companies from advertising on their network.
He shared a screen shot showing link selling services and companies selling links to link buyers. But is it just expanded keyword match or a new change in AdWords policy. Truth is, I never knew Google AdWords did not allow link buying/selling ads and I can't find a source that had said this (am I missing it?).
Here are some screen shot of ads for queries around these services:
[buy links] has no ads:
[buy pagerank] has ads mostly for books on Google PageRank:
[buy backlinks] has ads:
[link building] has ads:
[buy links for seo] also has ads:
Is this new? I am not sure, to be honest. Of course, the ethical question of if Google should take money from advertisers selling services against their guidelines is another topic.
Forum discussion Google+.