It's good that they're investigating the "insider dealing" varient of citation boosting but I haven't seen anything around excess self or chain-citing, which I

It's good that they're investigating the "insider dealing" varient of citation boosting but I haven't seen anything around excess self or chain-citing, which I always viewed as a more common offense. Obviously follow-up papers are a good thing, but I've known several authors that aim for long chains of follow-up papers (or summarizing several chains) purely for boosting citation numbers. The idea being that if it's a hot topic their paper will be caught in the crossfire regardless of whether it truly merits a citation.