Google has attempted to boost its ability to target TV ads by striking a deal to use detailed demographic data about TV audiences from Nielsen.

Nielsen’s data covers TV viewers’ ages, gender and marital status, and will be added to the information Google already gleans from set top boxes.

Google began selling TV ads earlier this year, buying up ad time on EchoStar’s satellite network and Astound’s cable TV service. It then resells these slots to advertisers via an auction system.

According to Keval Desai of Google, the Nielsen data is the ‘missing piece of puzzle’ for the company as it attempts to bring its talents at online ad targeting to TV.

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