Here is the new list of guidelines:
- Snippets must not be written or provided by the business or content provider unless they are genuine, independent, and unpaid editorial reviews.
- Reviews must allow for customers to express both positive and negative sentiments. They may not be vetted by the business or restricted by the content provider based on the positive/negative sentiment of the review before submission to Google.
- Reviews cannot be template sentences built from data or automated metrics. For example, the following is not acceptable: “Based on X number of responses, on average people experienced X with this business.”
- Reviews for multiple-location businesses such as retail chains or franchises can only be submitted for the specific business location for which they were written. In other words, reviews for multiple-location businesses cannot be syndicated or applied to all business locations of the same company.
- Aggregators or content providers must have no commercial agreements paid or otherwise with businesses to provide reviews.
- Do not include reviews that are duplicate or similar reviews across many businesses or from different sources.
- Only include reviews that have been directly produced by your site, not reviews from third-party sites or syndicated reviews.
The big change here is that when you include third-party syndicated reviews that are not “directly produced by your site,” you should not mark up those reviews with schema. Only “directly produced by your site, not reviews from third-party sites or syndicated reviews” should be marked up, according to these guidelines.
This may impact a large number of websites that have implemented local reviews markup.
You should read all the new guidelines above, but again, the biggest change and the one that probably will have the most impact right now is the third-party prohibition.