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BitTorrent is the most popular P2P content delivery application where individual users share various type of content with tens of thousands of other users. The growing popularity of BitTorrent is primarily due to the availability of valuable content without any cost for the consumers. However, apart from required resources, publishing (sharing) valuable (and often copyrighted) content has serious legal implications for users who publish the material (or publishers). This raises a question that whether (at least major) content publishers behave in an altruistic fashion or have other incentives such as !nancial. In this study, we identify the content publishers of more than 55K torrents in two major BitTorrent portals and examine their behavior. We demonstrate that a small fraction of publishers is responsible for 67% of the published content and 75% of the downloads. Our investigations reveal that these major publishers respond to two different pro!les. On the one hand, antipiracy agencies and malicious publishers publish a large amount of fake !les to protect copyrighted content and spread malware respectively. On the other hand, content publishing in BitTorrent is largely driven by companies with !nancial incentives. Therefore, if these companies lose their interest or are unable to publish content, BitTorrent traf!c/portals may disappear or at least their associated traf!c will be signi!cantly reduced. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for pro!t or commercial advantage and that copies bear this notice and the full citation on the !rst page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior speci!c permission and/or a fee.