An Empirical Study of the Patent Prospect Theory : An Evaluation of Antispam Patents

This paper is an empirical study of Edmund Kitch's patent prospect theory, based on an evaluation of antispam patents. The paper is thus a contribution to the wider debates about the benefits and costs of patents in general, and of software patents in particular. The antispam patent prospect has been selected for the study because this sector of the software industry was formed in the last decade, when software patents were routinely available, and the sector is sufficiently small that all known antispam patents have been individually evaluated and a majority of major players in the industry examined - including open-source firms. The paper concludes that the antispam patent prospect has facilitated the orderly development of the industry by encouraging diverse antispam solutions, discouraging technology appropriation by reverse engineering, and fostering a market for antispam technologies. It is argued that the patent environment has helped rather than hindered small, innovative, first-mover firms in protecting and marketing their technologies. It is also shown that the propriety and open-source modes of software delivery are not mutually exclusive, that collaboration takes place, and that both can derive benefit from the patent system