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Mark Zuckerberg

After cutting off data access for Wonder, a social search app from Russian search engine Yandex, Facebook explained today that if you’re building an app that “replicates” its “core functionality,” its data stream is not for the taking.

“For … apps that are using Facebook to either replicate our functionality or bootstrap their growth in a way that creates little value for people on Facebook, such as not providing users an easy way to share back to Facebook, we’ve had policies against this that we are further clarifying today,” wrote Justin Osofsky, Facebook’s director of platform partnerships and operations, in a blog post.

Osofsky explained that Facebook wants to provide resources to any developer who wants to build an app for the social network. He added that Facebook wants to make an environment in which it is easy for developers to create social experiences that are equally as easily shared across the network.

A Yandex spokesperson told VentureBeat via email last night, “We are in touch with Facebook to figure out on reasons and ways to solve the problem. As of now, any new Wonder user who is trying to sign up with their Facebook’s account in Wonder gets the notification by Facebook ‘An error occurred. Please try again later.’ Users who has already been signed up can still ask questions, but the Facebook data will not be updated. Instagram, Foursquare and Twitter data are being updated normally.”

Wonder, which took Facebook’s data and used it in search results evidently didn’t fit the bill. The company tried to head off Facebook by pointing out Facebook’s policy to not provide data to search engines. It then explained that Wonder is not a search engine but a personal assistant.

Facebook also recently shut down data access to voice mail app Voxer, which let you find your friends through Facebook, but it didn’t provide obvious ways to share back to the social network.

The company’s new Platform Policy section 1.10 now reads:

“Reciprocity and Replicating core functionality: (a) Reciprocity: Facebook Platform enables developers to build personalized, social experiences via the Graph API and related APIs. If you use any Facebook APIs to build personalized or social experiences, you must also enable people to easily share their experiences back with people on Facebook. (b) Replicating core functionality: You may not use Facebook Platform to promote, or to export user data to, a product or service that replicates a core Facebook product or service without our permission.”

Mark Zuckerberg image via Meghan Kelly/VentureBeat

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