By "B2B adtech" I mean "sells ads to businesses". This includes not just adsense, but adwords as well. Whether the ad is served on Google's sites or elsewhere,

By "B2B adtech" I mean "sells ads to businesses". This includes not just adsense, but adwords as well. Whether the ad is served on Google's sites or elsewhere, it's a business paying for it. Not that this semantic point makes any difference either way. Google is an ad business that happens to make consumer products.