Verifying Identity as a Social Intersection

20 Pages Posted: 20 May 2019

See all articles by Nicole Immorlica

Nicole Immorlica

Microsoft Research

Matthew O. Jackson

Stanford University - Department of Economics; Santa Fe Institute

E. Glen Weyl

Plural Technology Collaboratory, Microsoft Research Special Projects; Plurality Institute; GETTING-Plurality Research Network

Date Written: April 20, 2019


Most existing digital identity solutions are either centralized (e.g., national identity cards) or individualistic (e.g., most “self-sovereign” identity proposals). Outside of digital life, however, identity is typically social (for instance, “individual” data such as birthdate is shared with parents) and intersectional (viz., different data and trust are shared with different others). We formalize these ideas to provide a more robust and realistic framework for decentralized identity. We build upon the concepts web-of-trust and social collateral, from cryptography and economics, to provide a system of defining, verifying, and making use of identity through networks. We exploit the redundancy created by intersectionality together with the fragmentation of identity suggested by self-sovereign schemes to minimize social collateral required for verification. We exploit the probabilistic structure of Bloom filters to provide uniqueness proofs to prevent Sybil attacks while conveying minimal compromising information to verifiers. We discuss applications to “proof-of-personhood” blockchains and Radical Markets.

Keywords: Identity, Decentralized Identity, Social Identity, Intersectional, Network, Web of Trust, Privacy, Cybersecurity, Blockchain, Proof-of-Personhood, Social Collateral

JEL Classification: D85, Z13, P48

Suggested Citation

Immorlica, Nicole and Jackson, Matthew O. and Weyl, Eric Glen, Verifying Identity as a Social Intersection (April 20, 2019). Available at SSRN: or

Nicole Immorlica

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Matthew O. Jackson (Contact Author)

Stanford University - Department of Economics ( email )

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Santa Fe Institute

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Eric Glen Weyl

Plural Technology Collaboratory, Microsoft Research Special Projects ( email )

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Plurality Institute ( email )

GETTING-Plurality Research Network ( email )

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