Vertical restraints come in a glittering menu of exceptional variety, including resale price maintenance (RPM), tying, exclusive dealing, requirements contracts, "best efforts" clauses, full-line forcing, airtight and nonairtight exclusive territories, customer restrictions, areas of primary responsibility, profit-passover provisions, restrictions on locations of outlets, and dual distribution. Firms sometimes combine vertical restraints into packages. The great variety of individual and combined vertical restraints complicates the discovery of market effects. Indeed, identifying what restraint(s) a given firm is using at any particular time can be difficult.
Do the DOJ Vertical Restraints Guidelines Provide Guidance?, 32 Antitrust Bull. 609 (1987)