IKP Working Group Meeting Note
15 January 2026
Block 14 Session Planning
We kicked off with session planning for Block 14. IKP will lead or co-lead the following:
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IKP: Post-Quantum Cryptography (PQC) — establishing a competition framework for PQC standards in blockchain, with ETH/BTC as critical contributors.
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IKP: Privacy Enhanced Authentication and Key Management
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IKP: Accountable Wallet
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IKP: Proof of Personhood — discussed at depth today.
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IKP + FASE: Forensics and Analysis — Toward a Common Lexicon for Harmful On-Chain Activities
Proof of Personhood: Sharpening the Definitions
The bulk of today’s session focused on tightening our conceptual foundations for the Proof of Personhood working group item. We’re conducting a case comparison study across Gitcoin Passport, zkPassport, human tech, first person project and World ID to understand where proof of personhood ends and identity systems begin.
The Core Triangle
We explored whether proof of personhood requires three interdependent properties:
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Humanity — the “bot or not” primitive
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Uniqueness — preventing the same human from registering multiple times
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Identity — the system-defined register of attributes
A key insight: systems that prove humanity without uniqueness remain gameable. Uniqueness is a rate-limiting factor. This led us to propose the term “proof of unique humanness” as the stronger primitive.
Constraints as Definitions
We found that attack vectors help sharpen definitions:
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Uniqueness is a spatial question — are you registered once?
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Liveness is a temporal question — are you present now?
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Privacy (via selective disclosure) is what prevents linkability and reconstruction attacks
A true proof of personhood should not reveal identifiers that are referenceable or useful for correlation — distinguishing it from proof of identity.
Identifiers vs Identity
Identifiers are personal data. Composable, they become identity. The governance of which identifiers anchor uniqueness is a design choice, not a technical inevitability.
We also touched on edge cases: What happens when states issue passports for people who don’t exist? (Espionage, error, fraud.) Biometrics become the control mechanism.
Agents, Reputation, and Duality
A social media platform requiring World ID verification surfaced interesting questions:
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Users shouldn’t be limited to one account
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But reputation and rate-limiting across accounts should converge
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The human is the “gap in the middle”
This leads to pairwise pseudonymous identifiers — reputation accrues to the platform-specific identifier, not the root identity. Global reputation implies proof of identity, not personhood.
We discussed the “oneness risk”: if everything collapses to a single identifier, we enable censorship and total reconstruction. This risk extends to agents as well. Why duality matters — why it must be two (agentprivacy) to mitigate reconstruction of the personhood credential risk— for personhood-delegated agents, of which will be explored in further discussions.
While we raised reputation systems there was a consensus that this may be out of scope and expand /dilute the paper: ‘There are many different approaches and strategy with respect to reputation… And it is only “one” kind of application of PoP…’
Expanding the Case Studies
We’re broadening our resource gathering to include additional proof of personhood approaches, and will open to contributors of others undiscovered or those already on this list.
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WorldID
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Human.Tech — Human Passport
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Billions Network
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Web of Trust
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Kleros / Proof of Humanity
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BrightID
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First Person Project - trust graph
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Humanity Protocol — palm scan biometrics
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[…]
If you represent or have insight into these or have other approaches, we welcome your participation in the comparative analysis.
ACTIONS:
Contributions welcome. Reach out if you’d like to participate in the working group.
-Mitchell, IKP co-chair @privacymage
Our next working group call will be in two weeks and the public workshop shared between IKP and FASE working groups (details to be linked soon)
the topic is:
IKP + FASE: Forensics and Analysis — Toward a Common Lexicon for Harmful On-Chain Activities
- any showcase or open AMA on the documents and progress on working items, such as the proof of personhood paper.
+Block 14 workshop preparations.
