Anonymity is an important principle online. However, malicious actors have long used misleading identities to conduct fraud, spread disinformation, and carry out other deceptive schemes. With the advent of increasingly capable AI, bad actors can amplify the potential scale and effectiveness of their operations, intensifying the challenge of balancing anonymity and trustworthiness online. In this paper, we analyze the value of a new tool to address this challenge: "personhood credentials" (PHCs), digital credentials that empower users to demonstrate that they are real people -- not AIs -- to online services, without disclosing any personal information. Such credentials can be issued by a range of trusted institutions -- governments or otherwise. A PHC system, according to our definition, could be local or global, and does not need to be biometrics-based. Two trends in AI contribute to the urgency of the challenge: AI's increasing indistinguishability from people online (i.e., lifelike content and avatars, agentic activity), and AI's increasing scalability (i.e., cost-effectiveness, accessibility). Drawing on a long history of research into anonymous credentials and "proof-of-personhood" systems, personhood credentials give people a way to signal their trustworthiness on online platforms, and offer service providers new tools for reducing misuse by bad actors. In contrast, existing countermeasures to automated deception -- such as CAPTCHAs -- are inadequate against sophisticated AI, while stringent identity verification solutions are insufficiently private for many use-cases. After surveying the benefits of personhood credentials, we also examine deployment risks and design challenges. We conclude with actionable next steps for policymakers, technologists, and standards bodies to consider in consultation with the public.

翻译：匿名性是网络空间的重要原则。然而，恶意行为者长期利用误导性身份实施欺诈、传播虚假信息并进行其他欺骗活动。随着人工智能能力日益增强，不良行为者能够扩大其操作的潜在规模和效力，加剧了平衡网络匿名性与可信度的挑战。本文分析了一种应对此挑战的新型工具的价值："人格凭证"——这种数字凭证使用户能够向在线服务证明自己是真实人类而非人工智能，且无需披露任何个人信息。此类凭证可由政府或其他可信机构颁发。根据我们的定义，人格凭证系统可以是本地或全球性的，且无需基于生物特征识别。人工智能的两大发展趋势加剧了该挑战的紧迫性：一是人工智能与人类在网络中的区分度日益模糊（如逼真的内容与虚拟形象、代理行为），二是人工智能的可扩展性不断增强（即成本效益与可访问性提升）。借鉴匿名凭证与"人格证明"系统的长期研究，人格凭证为人们在网络平台上提供了一种传递可信度的方式，并为服务提供商提供了减少恶意行为者滥用的新工具。相比之下，现有的自动化欺骗应对措施（如验证码）难以抵御复杂的人工智能，而严格的身份验证解决方案对许多应用场景而言又缺乏足够的隐私保护。在探讨人格凭证的益处后，我们也审视了其部署风险与设计挑战。最后，我们为政策制定者、技术人员和标准机构提出了可供公众咨询后考虑的具体后续步骤。