Currently, the 20-percent rule — which went into effect on January 15th — applies to Page Post ads, Sponsored Stories and Promoted Posts. When it comes to Facebook ads, a good rule of thumb to go by is this: If you pay money to promote a piece of content, or you create an ad within Facebook’s Ads Manager, the 20-percent text rule applies. (The rule also applies to Cover Photos even though they are not ads.)
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