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The U.S. Patent and Trademark Office rejected the airline's request to trademark the slogan "The world's most trusted airline," saying the motto is "not inherently distinctive, but rather is merely laudatory and descriptive."
The airline has six months to appeal.
Don't feel sorry for Delta. The airline can always revisit one of 22 other trademarks and slogans it has adopted since the 1920s, including "The airline with the big jets" (1959), "We love to fly and it shows" (1987) "Ready when you are" (1992) and the latest, "Keep climbing."