When Google (NSDQ: GOOG) first launched its Google Voice call syncing and voicemail service, the company said it would run without ads. But a patent reveals that the company is at least thinking about monetizing the service with ringback ads, or ads that play instead of the normal “ring” a user hears at the start of a call.
According to InfoWeek, the ads would be sold auction-style on a “cost-per-call” basis. Advertisers would be charged by a metric called a “listen-through” (much like the click-through), depending on how much of the ad the user heard.
Google Voice product manager Vincent Paquet told InfoWeek that the company was looking to support the service with some form of advertising — which makes sense if Google is really trying to compete against the carriers for their own voice services.
The only caveat will be whether Google Voice users will be reluctant to use it if they know that their callers will be forced to listen to an ad first. (Then again — people already put up with ads in the majority of Google’s other free products).

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