Do not run competitive contextual text ad or search services on the same site

which offer Google Adsense competition in their field. Never try to create link structures resembling the adsense ads. Never use other competitive search tools on the same pages which have Adsense powered Google search. They do allow affiliate or limited-text links. Update: Google has allowed you to run contextual advertising like Yahoo ads, Chitika etc provided the ads do not resemble Adsense ads.