According to a recent study completed by Multichannel Merchant and Direct magazines, 61 percent of business-to-business marketers have formal permission practices for collecting email addresses, while 93 percent of consumer marketers say they have formal practices in place, eMarketer reports (via MediaBuyerPlanner). Sixty percent of the consumer marketers surveyed reported using a single opt-in method of gathering email addresses, while 7 percent used a double opt-in method. Of the business marketers surveyed, 26 percent used single opt-in methods, and just three percent used the double opt-in method.