Another legal principle relevant to market definition is the concept of a 'targeted' or 'price discrimination' market. According to the Merger Guidelines: When examining possible adverse competitive effects from a merger, the Agencies consider whether those effects vary significantly for different customers purchasing the same or similar products. Such differential impacts are possible when sellers can discriminate, e.g., by profitably raising price to certain targeted customers but not to others. [...] When price discrimination is feasible, adverse competitive effects on targeted customers can arise, even if such effects will not arise for other customers. A price increase for targeted customers may be profitable even if a price increase for all customers would not be profitable because too many other customers would substitute away. U.S. Dep't of Justice & FTC Horizontal Merger Guidelines §3 (2010) (hereinafter Merger Guidelines).
Defining a market around a targeted consumer, therefore, requires finding that sellers could 'profitably target a subset of customers for price increases . . .' See Sysco, 113 F. Supp. 3d at 38 (citing Merger Guidelines Section 4.1.4.). This means that there must be differentiated pricing and limited arbitrage.