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Greylock Partners VC David Sze is no doubt thrilled to have been caught endorsing Blackberry via Facebook. Such "social ads" are the very reason his firm invested in the social network. If you're more chary of inflating Facebook's valuation while giving a thumbs-up to its advertisers, here's how to keep Facebook's endorsement ads from appearing in your friends' News Feed.

This image was lost some time after publication.
This image was lost some time after publication.
This image was lost some time after publication.
This image was lost some time after publication.
This image was lost some time after publication.