Google has updated its guidelines for sites with explicit content to now specify that ecommerce sites must "label adult products in ecommerce feeds or markup." There is also a new section at the bottom of the help document titled, "For Google Shopping features."

Google added this new line to the document:

For ecommerce sites: label adult products in ecommerce feeds or markup.

Google also added this new section to the bottom of the document:

For Google Shopping features: label adult products in ecommerce feeds or markup

If you're optimizing your product listings to appear in Google Shopping features and your products are considered adult-oriented according to Google's adult-oriented content policy, label them in your Merchant Center feeds with the adult attribute or with hasAdultConsideration structured data markup. This label doesn't affect your site's visibility in organic web search results.

I believe Google also updated the respective Merchant Center help documentation around these changes.

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