https://techcrunch.com/2023/05/03/blue-verified-checkmarks-are-coming-to-gmail/

Google is going to start displaying a blue checkmark next to select senders’ names on Gmail to verify their identity, the company announced on Wednesday. The new blue checkmarks will automatically appear next to companies that have adopted Gmail’s existing Brand Indicators for Message Identification (BIMI) feature.

The BIMI feature, which rolled out in 2021, requires senders to use strong authentication and verify their brand logo in order to display a brand logo as an avatar in emails. Users will now see a checkmark icon for senders that have adopted the BIMI feature. Google says this update will help users identify messages from legitimate senders versus impersonators.