In the UK, under its purely municipal law, there is a presumption that retail price management agreements are against the public interest, and therefore unenforceable. The law does, however, provide for the presumption to be overcome by evidence to the contrary, and in the case of publishers and booksellers, vertical retail price management has been held enforceable. The UK is, of course, a member of the European Union which takes a stronger stand against retail price management, and pursuant to the articles of the European Commission, it is their standards that apply to covered cross-border transactions.
In the U.S., there have been swings back and forth through much of the 20th century, but current Federal law (since 2007) applies the "Rule of Reason" to retail price management arrangements, and a retail pricing scheme will be enforced if it is not anti-competitive. The Supreme Court recognized that competition often is enhanced by matters other than price (after-sale support, strong warranty, etc.), and it may well be reasonable to require a minimum price to support an overall more competitive position.
Those who find the public policy aspects of this question interesting may wish to read the now definitive opinion of the U.S. Supreme Court, http://www.supremecourt.gov/opinions/06pdf/06-480.pdf
In the U.S., there have been swings back and forth through much of the 20th century, but current Federal law (since 2007) applies the "Rule of Reason" to retail price management arrangements, and a retail pricing scheme will be enforced if it is not anti-competitive. The Supreme Court recognized that competition often is enhanced by matters other than price (after-sale support, strong warranty, etc.), and it may well be reasonable to require a minimum price to support an overall more competitive position.
Those who find the public policy aspects of this question interesting may wish to read the now definitive opinion of the U.S. Supreme Court, http://www.supremecourt.gov/opinions/06pdf/06-480.pdf