8/16/2015 Yahoo! Finance
America Movil <AMXL.MX> said on Sunday it removed roaming charges on calls to and data in the United States for 40 million Mexican prepay clients as it gears up to prevent new rival AT&T Inc. stealing market share on its home turf.
The company, owned by the family of billionaire Carlos Slim, said calls made to the United States by prepaid customers on “Amigo Optimo” and “Optimo Plus” plans would now be charged local rates. The same would apply when using data in the United States.