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Potential use cases: third-party chat embeds, third-party map embeds, third-party payment embeds, subre-
source CDN load balancing, headless CMS providers, sandbox domains for serving untrusted user content,
third-party CDNs using cookies for access control, third-party API calls that require cookies on requests,
embedded ads with state scoped per publisher.

Learn more about CHIPS

4. Use Storage Access API and Related Website Sets

Where your third-party cookie is only used across a small number of related sites, then you may consider using Related
Website Sets (RWS) to allow cross-site access for that cookie within the context of those defined sites.

To implement RWS, you will need to define and submit the group of sites for the set. To ensure that the sites
are meaningfully related, the policy for a valid set requires grouping those sites by: associated sites with a
visible relation to each other (e.g. variants of a company's product offering), service domains (e.g. APIs,
CDNs), or country-code domains (e.g. *.uk, *.jp).

Sites can use the Storage Access API to either request cross-site cookie access using requestStorageAccess
() or delegate access using requestStorageAccessFor(). When sites are within the same set, the browser will
automatically grant access and cross-site cookies will be available.

This means that groups of related sites can still make use of cross-site cookies in a limited context, but do
not risk sharing third-party cookies across unrelated sites in a way that would allow cross-site tracking.

Potential use cases: app-specific domains, brand-specific domains, country-specific domains, sandbox do-
mains for serving untrusted user content, service domains for APIs, CDNs.