Simon Willison’s Weblog

Group Membership Protocol. Martin Atkins’ proposal for a simple “is OpenID X a member of group Y?” protocol, useful for whitelists that can scale to handle large numbers of entries.

Posted 22nd January 2007 at 8:27 am

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GPT-5.2 - 11th December 2025
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martin-atkins 7 openid 213 whitelisting 7

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