With at least one of the company's partners, smartphone owners opt into location mapping, and in other cases, customers have the ability to opt out, King said.
Clear Channel has no ability to determine personal information such as the age and gender of people who see its billboards, King added. "The data providers can inform us by sharing, for example, that I-95 in Florida has a high percentage of young families traveling to Disney World," he said. "And some of these travel paths may run contrary to where an advertiser might think these groups congregate or pass."
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