XM Satellite Radio, Washington, said numerous media buying agencies and clients like Allstate Corp., AT&T Corp. and Discovery Networks already have signed on as charter advertisers, even though satellite radio won't hit the airwaves until spring 2001. Grey Advertising, Leo Group's Starcom
Worldwide, Ogilvy & Mather, J. Walter Thompson USA, Young & Rubicam's Media Edge and Zenith Media
are among the agencies committed to buying blocks of ad time on the subscription radio service's national channels. XM also said it has signed an agreement with Clear Channel Communications subsidiary Premiere Radio Networks to be XM's sales rep.
Copyright February 2000, Crain Communications Inc.