French newspaper publishers have been pushing for the law, saying it is unfair that Google receives advertising revenue from searches for news.

BBC: Google threatens French media ban over proposed law

The other two cases concerned lawsuits in federal court by a New Jersey bank against the state of Florida for infringing its patent on a college-savings scheme and for false advertising and unfair competition under a federal trademark law.

ECONOMIST: The Supreme Court

Siskind, a founding partner at the law firm Harvey Siskind LLP in San Francisco, who isn't involved in the case, says if Macy's doesn't win the case under the doctrines of trademark law, it is possible the retailer may be able to win the case on other grounds, such as unfair competition or false advertising.

WSJ: Basing a Business on an Old Brand? Check the Trademarks

In the other Florida case, Justice Antonin Scalia, the court's most vocal champion of a strict textual reading of the constitution, argued that Congress was wrong to regard damage to an ongoing business from the false advertising or unfair competition of a state agency as an unlawful deprivation of property barred by the 14th amendment.

ECONOMIST: The Supreme Court

Plaintiff lawyers argue they are doing a public service by enforcing laws against false advertising and other unfair trade practices.

FORBES: Magazine Article

Tiffany and Company alleges trademark infringement, counterfeiting, unfair competition, injury to business reputation, false advertising and deceptive business practices.

WSJ: Tiffany sues Costco over engagement rings

The company is also worried that Google's dominance in search and advertising allows it to dictate terms to advertisers, and gives it an unfair advantage over its smaller rivals.

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