Normally our SKUs are listed something like this: "76281646965407111" but I've been noticing some seemingly random ones showing up like this: "gid=76281646965407111". We're definitely not manually adding it. I do use the Google Merchant Product Lister by DLSS as well as his CSV Product Data Utility but I don't know if those would be the culprit. Would Google be able to change some of these? The Merchant center does crawl the site. Do I need to do delete the "gid=" from these?

Hi DavidX
What I would do is have a look at the output of the Google Merchant Product Lister for that example product, and also use a structured data validator like this one to make sure that all your output is correct...
https://developers.google.com/search/docs/appearance/structured-data

Vince

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