When customers seek out online deals, it seems like a win for everybody: Brands, retailers, dealers, and distributors sell more goods, and buyers get a bargain. What’s not to like? Here’s the problem: Lured by rock-bottom online prices, customers often end up dealing with disreputable digital resellers that mistreat them, which can erode brand equity and undermine authorized sellers. For brands selling in the United States and Canada, there is a potent countermeasure: crafting and enforci...