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Atproto Trademark Policy

Trademark policy for the AT Protocol.

Last Updated: July 2, 2026

Contents

1. Purpose

Bluesky Social PBC ("Bluesky") owns the AT Protocol, atproto, and atprotocol trademarks associated with the Authenticated Transfer Protocol (“AT Protocol”).

The AT Protocol is an open protocol for building a multi-stakeholder, decentralized social networking ecosystem. It is designed so that developers, researchers, services, communities, and users can create interoperable systems and services across the protocol ecosystem.

We want the AT Protocol marks to be widely and responsibly used by the community. This policy is designed to make ordinary, good-faith use easy, while preserving the AT Protocol trademarks as reliable indicators of the actual AT Protocol specification and the ecosystem built around it.

This policy has three goals:

  1. Encourage adoption. Developers, researchers, projects, and communities should be able to refer to the AT Protocol, build on it, teach it, discuss it, and describe interoperability with it.

  2. Avoid confusion. People should be able to tell the difference between the AT Protocol itself, Bluesky, independent projects, compatible services, forks, experiments, and community efforts.

  3. Protect the ecosystem. Trademark rights help prevent scams, impersonation, confusing forks, fake certification claims, misleading services, and uses that would make the marks unreliable for the community.

Bluesky is committed to the long-term openness and decentralization of the AT Protocol. As the ecosystem matures, Bluesky may transfer ownership or stewardship of the AT Protocol marks to an independent foundation, standards body, or other governance structure designed to preserve continuity for the community.

2. Marks Covered by This Policy

This policy covers the following trademarks:

  • AT Protocol
  • atproto
  • atprotocol

It also applies to similar variations of those marks when used in a way that may cause confusion about source, sponsorship, endorsement, official status, or protocol compatibility.

Trademarks associated with the Bluesky app, including Bluesky, bsky, and the Bluesky butterfly logo are covered by the separate Bluesky Trademark Policy.

3. Uses That Do Not Require Permission

You may use the AT Protocol marks without permission for the following uses, provided your use is accurate, non-misleading, and complies with this policy.

3.1 Referring to the protocol

You may use AT Protocol, atproto, or atprotocol to refer to the protocol specification, reference implementations, developer documentation, or the ecosystem of software and services built on the protocol.

Examples:

  • "The AT Protocol is a decentralized social networking protocol."
  • "This library helps developers work with atproto data repositories."

3.2 Compatibility and interoperability statements

You may accurately state that a product, service, library, tool, or project implements, supports, integrates with, or is compatible with the AT Protocol.

Examples:

  • "Skyline is a social app built on the AT Protocol."
  • "This SDK supports atproto repositories."
  • "This tool works with AT Protocol PDSes."

3.3 Descriptive "built on" language

You may use descriptive phrases such as:

  • "built on AT Protocol"
  • "powered by atproto"
  • "compatible with the AT Protocol"
  • "for use with atprotocol"

Your own product, project, or organization name must be at least as prominent as the AT Protocol mark.

3.4 Documentation, tutorials, and educational materials

You may use the marks in documentation, tutorials, explainers, blog posts, videos, courses, presentations, sample code, and educational materials about the AT Protocol.

3.5 Research, commentary, criticism, and news

You may use the marks in academic research, technical papers, commentary, criticism, news reporting, comparative analysis, and similar expressive uses.

3.6 Open-source project descriptions

You may use AT Protocol, atproto, or atprotocol in a README, package description, repository description, issue, pull request, or documentation to describe how a project relates to or implements the AT Protocol.

Examples:

  • "An atprotocol feed generator."
  • "A TypeScript library for AT Protocol repositories."
  • "A testing tool for atproto Lexicons."

3.7 Package, module, and repository names

You may use AT Protocol, atproto, or atprotocol in package, module, crate, repository, or command names when the use accurately describes compatibility, implementation, or developer tooling, and does not suggest that the package is official.

Examples generally allowed:

  • atproto-feed-tools
  • atproto-client
  • example-atproto-client
  • relay-utils-for-atproto

Examples requiring review or changes:

  • official-atproto
  • atproto-core
  • atproto-v2
  • AT Protocol Foundation SDK

3.8 Protocol identifiers, handles, NSIDs, and subdomains

You do not need permission merely because AT Protocol, atproto, or atprotocol, or a related string appears in:

  • code comments;
  • protocol namespace strings;
  • Lexicon schemas;
  • NSIDs;
  • at:// URIs;
  • handles;
  • DID documents;
  • subdomains used descriptively or technically.

For example, using atproto.example.com as a subdomain for documentation, testing, or developer resources does not require permission if it does not imply that the site is official.

3.9 Community discussion

You may use the marks in online forums, chat rooms, social media, mailing lists, community calls, conference talks, and similar discussions about the AT Protocol.

3.10 Community events

You may use the marks in the name or materials of a free, community-focused, non-commercial meetup, hackathon, tutorial, or similar event directly related to building on or learning about the AT Protocol.

Your materials must make clear who is organizing the event and must not imply that any standards development organization, or Bluesky, officially runs, sponsors, or endorses the event.

3.11 Personal or small-group merchandise

You may make AT Protocol or atproto-themed merchandise for yourself or a small group of community members if the merchandise is not sold.

4. Uses That Require Permission

The following uses require written permission from Bluesky. Permission will generally be granted for good-faith uses that support the open AT Protocol ecosystem and do not create confusion.

To request permission, email trademarks@atproto.com with:

  1. Your name and organization, if any.
  2. The mark(s) you want to use.
  3. A short description of how and where you want to use them.
  4. Any relevant link, mockup, event page, draft material, or domain name.
  5. Whether the use is commercial.

Any email approving a request will identify the approved marks and approved use. Unless stated otherwise in writing, approved uses are subject to the Standard AT Protocol Trademark Permission Terms in Appendix A.

4.1 Registered domain names

You need permission to register or use a second-level registered domain name that incorporates AT Protocol, atproto, or atprotocol, or a confusingly similar variation as a source-identifying part of the domain.

Examples requiring permission:

  • atproto-tools.com
  • theatprotocol.org
  • atproto.cloud

This section does not apply to ordinary protocol use of domain names as handles, NSIDs, DID-related identifiers, at:// URIs, or descriptive subdomains.

Examples not requiring permission by themselves:

  • atproto.docs.example.com as technical documentation for an independent project
  • atproto.example.com for a clearly unofficial developer page
  • com.example.atproto.feed as an NSID

4.2 Commercial events

You need permission before using any AT Protocol mark in the name, primary branding, or promotional materials of a paid, sponsored, or commercial conference, meetup, hackathon, training, or similar event.

Descriptive references do not require permission.

Example requiring permission: “AT Protocol Developer Summit, presented by [Company]."

Example not requiring permission: "A hackathon for developers building on the AT Protocol."

4.3 Merchandise for sale

You need permission to sell physical or digital merchandise bearing AT Protocol marks.

Bluesky will generally approve community-aligned merchandise if:

  • the use is clearly unofficial;
  • the mark is used accurately;
  • the seller clearly and accurately states whether any proceeds benefit the AT Protocol project, or another community effort.

4.4 Product, service, organization, or company names

You need permission to use AT Protocol, atproto, or atprotocol as a primary brand identifier in a product name, service name, organization name, company name, or trade name.

Examples requiring permission:

  • "Atproto Cloud"
  • "AT Protocol Hosting"
  • "Atproto Labs"
  • "The AT Protocol Company"

Examples generally allowed without permission:

  • "Cloud services for atproto"
  • "[Your Project] hosting for AT Protocol services"
  • "[Your Project] SDK for atproto"

4.5 Conformance, Compatibility, Compliance, and Test-Suite Claims

You may make truthful, specific statements that your product, service, software, or implementation supports, implements, conforms to, or passes tests for the AT Protocol or particular parts of it, provided you clearly identify the basis for the claim and who is making it.

Allowed without permission, if true:

  • "[Product] implements the AT Protocol [specification/version]."
  • "[Tool] passes the [name/version] atproto test suite maintained by [maintainer]."
  • "[Implementation] conforms to [specific published specification or test profile]."

You need prior written permission for claims that imply any official certification, approval, endorsement, official status, or a formal relationship with Bluesky.

Examples requiring permission:

  • "AT Protocol Certified"
  • "Official AT Protocol implementation"
  • "Certified by Bluesky"

If a claim is based on a third-party test suite, clearly identify the test suite and maintainer. If it is self-assessed, say so clearly.

4.6 Logos and design marks

If Bluesky publishes an official AT Protocol logo, badge, or design mark, use of that logo, badge, or design mark requires permission except where published brand guidelines expressly allow permissionless use.

Text references to AT Protocol, atproto, or atprotocol are governed by the other provisions of this policy.

5. Prohibited Uses

The following uses are not permitted.

5.1 False official status or endorsement

Do not use AT Protocol marks in a way that falsely suggests that your product, service, project, event, or organization has been officially sponsored, endorsed, approved, certified, or is officially affiliated with Bluesky.

5.2 Confusing modified protocol claims

Do not describe a substantially modified, incompatible, or competing protocol as AT Protocol, atproto, or atprotocol.

A project that implements a protocol incompatible with the AT Protocol must use its own distinct name. It may accurately state that it is "based on AT Protocol technology," "derived from AT Protocol," or "inspired by AT Protocol," if that is true and not misleading.

5.3 Misleading versions, forks, or successors

Do not use the marks in a way that suggests you are publishing an official successor, replacement, or new version of the AT Protocol without prior, express, written authorization.

Examples not permitted without authorization:

  • "AT Protocol v2"
  • "atproto-next"
  • "official AT Protocol fork"
  • "the new atprotocol standard"

5.4 Trademark registrations and ownership claims

Do not register, apply to register, or claim ownership of any trademark, trade name, service mark, logo, domain name, social media handle, or source identifier that incorporates AT Protocol marks or confusingly similar variations.

5.5 Scams, phishing, impersonation, and malicious activity

Do not use AT Protocol marks in connection with scams, phishing, malware, impersonation, credential harvesting, deceptive services, or other harmful or unlawful activity.

5.6 Logo modification

Do not alter, distort, recolor, combine, or modify any AT Protocol logo or design mark unless Bluesky's published brand guidelines or written permission expressly allow it.

6. Usage Guidance

These are style guidelines intended to help the community use the marks clearly and consistently. Bluesky will focus enforcement on uses that are confusing, misleading, or harmful, not on good-faith style differences.

Use AT Protocol, atproto, or atprotocol in public-facing materials where practical. Avoid variants like "at-proto," "AtProto," ot "AT-Protocol" when practical.

Your own project, product, service, or organization name should be at least as prominent as any AT Protocol mark.

Where there is a reasonable possibility of confusion, include a disclaimer such as: "[Project/Product/Event] is independent and is not affiliated with or endorsed by AT Protocol."

7. Relationship Between Code Licenses and Trademark Rights

The AT Protocol reference implementations, specifications, and related software may be available under open-source or permissive licenses. Those licenses govern use, modification, and distribution of code and specifications. They do not grant trademark rights.

You may fork, modify, and redistribute code as allowed by the applicable code license. That does not automatically give you the right to use AT Protocol, atproto, or atprotocol as the name or branding for a modified or incompatible protocol, product, service, or project.

8. Good Faith Safe Harbor

Bluesky recognizes that the AT Protocol is open and that community members may use the marks in good faith in ways that do not perfectly match this policy.

If your use is in good faith, broadly consistent with this policy, and not intended to deceive, defraud, impersonate, or misappropriate, Bluesky will ordinarily provide notice and a reasonable opportunity to fix the issue before taking any formal action.

This safe harbor does not apply to scams, phishing, impersonation, malicious activity, bad-faith registrations, or uses that intentionally mislead people about official status, compatibility, certification, or endorsement.

9. Reporting Misuse

If you become aware of a use of AT Protocol marks that appears confusing, misleading, abusive, or inconsistent with this policy, please report it to trademarks@atproto.com.

Do not send enforcement demands on Bluesky's behalf. Bluesky will review reports and determine the appropriate response.

10. Future Governance

Bluesky is committed to the long-term openness and decentralization of the protocol. As the protocol ecosystem matures, Bluesky may transfer ownership or stewardship of AT Protocol marks to an independent foundation, standards body, or other governance body.

Any transition will be designed to preserve:

  • broad community permissions;
  • continuity for existing good-faith uses;
  • protection against confusion, scams, and impersonation;
  • the ability to identify the actual AT Protocol specification and compatible implementations.

11. Revocation, Disclaimer, and Governing Law

11.1 Revocation

Bluesky may revoke permission granted under this policy if a use is confusing, misleading, harmful, inconsistent with this policy, or inconsistent with the purpose of preserving the AT Protocol marks for the open ecosystem.

Where appropriate, Bluesky will provide reasonable notice and an opportunity to cure before revocation.

11.2 No waiver

Nothing in this policy waives, limits, or relinquishes Bluesky's trademark rights. Bluesky's decision not to object to a particular use does not prevent Bluesky from objecting to other uses or later uses that are confusing, misleading, harmful, or inconsistent with this policy.

11.3 No warranty

Bluesky makes no representations regarding any third party's right to use AT Protocol marks. Permission to use the marks under this policy does not constitute a warranty of non-infringement. Bluesky assumes no liability arising from any permitted use.

11.4 Governing law

Any dispute arising from use of the marks is governed by the laws of the State of Delaware, and the parties consent to the exclusive jurisdiction of the state and federal courts in King County, Washington.

12. Contact

For trademark questions, permission requests, or misuse reports:

Email: trademarks@atproto.com

Appendix A: Standard AT Protocol Trademark Permission Terms

These Standard AT Protocol Trademark Permission Terms ("Terms") apply to trademark permission granted by Bluesky Social PBC ("Bluesky") in an approval email that references these Terms ("Approval Email"). By replying "I agree to the Standard AT Protocol Trademark Permission Terms," or by using any Licensed Marks after receiving the Approval Email, the recipient identified in the Approval Email ("Licensee") agrees to these Terms. "Licensed Marks" means the AT Protocol marks identified in the Approval Email. "Approved Use" means the specific use described in the Approval Email.

1. Grant of Permission

Bluesky grants Licensee a limited, non-exclusive, non-transferable, non-sublicensable, revocable license to use the Licensed Marks solely for the Approved Use and solely in accordance with these Terms and the AT Protocol Trademark Policy. Licensee shall not sublicense, assign, or transfer any rights granted under these Terms to any third party.

2. Quality Standards

Licensee acknowledges that the Licensed Marks represent the quality, reputation, and integrity of the AT Protocol ecosystem. Licensee shall:

2.1. Maintain a standard of quality in connection with the Approved Use that is consistent with the standards associated with the Licensed Marks, as reasonably determined by Bluesky.

2.2. Promptly comply with any written request from Bluesky to modify, correct, or cease any use of the Licensed Marks that Bluesky reasonably determines does not meet the standards of these Terms or the AT Protocol Trademark Policy.

2.3. Upon Bluesky's reasonable request, provide samples or descriptions of materials bearing the Licensed Marks for review.

3. Ownership

Licensee acknowledges that Bluesky is the sole owner of all right, title, and interest in and to the Licensed Marks, together with all goodwill associated with them. All use of the Licensed Marks by Licensee inures to the benefit of Bluesky. Nothing in these Terms grants Licensee any ownership interest in the Licensed Marks. Licensee shall not challenge, contest, or take any action inconsistent with Bluesky's ownership of the Licensed Marks.

4. Term and Termination

4.1. Term. These Terms are effective upon Licensee's acceptance and continue until terminated by either party.

4.2. Termination by Licensee. Licensee may terminate these Terms at any time by ceasing all use of the Licensed Marks and providing written notice to trademarks@atproto.com.

4.3. Termination by Bluesky. Bluesky may terminate these Terms (a) immediately upon written notice if Licensee breaches these Terms or the AT Protocol Trademark Policy, or (b) for any reason upon thirty (30) days' written notice to the email address used by Licensee in the permission request or acceptance reply.

4.4. Effect of Termination. Upon termination, Licensee shall immediately cease all use of the Licensed Marks and destroy or remove all materials bearing the Licensed Marks within fifteen (15) days. Sections 3, 4.4, and 5 survive termination.

5. General Provisions

5.1. Entire Agreement. These Terms, the Approval Email, and the AT Protocol Trademark Policy constitute the entire agreement between Bluesky and Licensee concerning the Approved Use.

5.2. Amendments. Bluesky may amend these Terms by publishing a revised version on the AT Protocol Trademark Policy page. Continued use of the Licensed Marks following publication of any amendment constitutes acceptance of the revised Terms.

5.3. Severability. If any provision of these Terms is held unenforceable, the remaining provisions remain in full force and effect.

5.4. No Waiver. Bluesky's failure to enforce any provision of these Terms does not constitute a waiver of that provision or of Bluesky's right to enforce it in the future.

5.5. Notices. Notices to Bluesky shall be sent to trademarks@atproto.com. Notices to Licensee shall be sent to the email address used by Licensee in the permission request or acceptance reply.