A number of journals which have demonstrated what the folks who publish the Impact Factors call “anomalous” citation patterns have been told that they will be barred from for a period of two years from appearing in the Journal Citation Report (JCR), which concocts and publishes the IFs. According to a post on the the Scholarly Kitchen, this business about anomalous citation behavior is a code word for ‘self citation’, which can occur in various ways. The crudest is the one in which editors hold a manuscript for ransom, by not accepting it until the bibliography contains more citations to that very journal. There are other ways. The JCR team got wind of these practices some time ago and to their credit have undertaken a policy of monitoring and punitive reaction by suspension in those case where systematic efforts to game the system have been detected.
The Impact Factor has been the subject of wide criticism, some of it here, but I think we have to hand it to the publishers of the JCR for trying hard to keep the tool, whatever its virtue and flaws, as honest as possible.
http://scholarlykitchen.sspnet.org/2012/06/29/citation-cartel-journals-denied-2011-impact-factor/