Digital Rights Management, or DRM, is a major concern for all premium content publishers. But how do you balance the need to protect your content with customer satisfaction and user-friendly experiences?One way may be through watermarking. Recently installed in J.K Rowling's Pottermore.com eBook collection, the technology lets the publisher "personalize" or watermark each purchase with the time of purchase and name of the purchaser. This then allows publishers to track any copyright infringement...