One less car is a slogan sometimes seen in Critical Mass rides on shirts, flyers and stickers. The slogan was originated around 1982 by cycling advocate Richard Rosenthal, in New York City, and given by him to New York's (then) bicycle advocacy organization, Transportation Alternatives (which has since expanded its portfolio to include pedestrians as well as cyclists). TA failed to protect it with a trademark or copyright. When it was pointed out to Specialized, which used the expression on a T-shirt they sold, that it had been the (unprotected) property of non-profit TA, they contributed $25 to TA. When Pearl Izumi used the expression on a T-shirt they sold and had it pointed out to them it had been TA's (unprotected) property, they declined to make a contribution to TA.
The expression was adopted by Critical Mass, a group in New York promoting use of the bicycle for transportation and spread to Critical Mass groups in other cities in the U.S. The expression was given international standing by carfree.net, headquartered in Prague, (now worldcarfree.net), publisher of carbusters online magazine and further spread by Critical Mass groups in Europe.