What are Pinterest's image requirements for pinning?

Hi, Brian!

From Pinterest's terms:
Post, upload, publish, submit, provide access to or transmit any Content that: (i) infringes, misappropriates or violates a third party’s patent, copyright, trademark, trade secret, moral rights or other intellectual property rights, or rights of publicity or privacy; (ii) violates, or encourages any conduct that would violate, any applicable law or regulation or would give rise to civil liability; (iii) is fraudulent, false, misleading or deceptive; (iv) is defamatory, obscene, pornographic, vulgar or offensive; (v) promotes discrimination, bigotry, racism, hatred, harassment or harm against any individual or group; (vi) is violent or threatening or promotes violence or actions that are threatening to any other person; or (vii) promotes illegal or harmful activities or substances.

That's the long, legal answer.

The short, "best practice" answer is that they recommend you pin images from their original source. This will hopefully ensure that the correct source URL is appended to the image - meaning that proper attribution will follow the image as it travels around Pinterest.

RE: technical requirements - I'm less clear on this, but have noticed that in some cases, Pinterest can't "see" images on certain web pages. There are also restricted use cases - Facebook, for instance. You can't pin an image directly from Facebook. I also read recently that, due to the issues around copyright and intellectual property, Pinterest released a way for site owners to opt out of having the images accessible for pinning. (http://blog.pinterest.com/post/17949261591/growing-up)

I hope this helps answer your question.

TKS!