Causal games might be defined as games small enough to be downloaded and/or web based (e.g., one of my favs, Desktop Tower Defense). How does piracy affect the causal game business? Over on Gamasutra, Reflexive's director of marketing Russell Carroll has posted a great article asserting that 92% of one game, the full version of Ricochet Infinity, were found to be playing pirated copies. A staggering percentage.
One way to fight the search-engine facilitated piracy is to work to remove the ever-expanding number of links to illegal copies, but in many cases improving the Digital Rights Management (DRM) system to be more secure can be more effective as it renders a large number of those links obsolete. This is tricky to be sure, because improving the security must be done without making the DRM so onerous that it keeps honest customers from purchasing games.