What each ISO standard actually covers (and the marketing copy you should ignore)
**ISO/IEC 27001:2022** is the foundation. It defines requirements for an Information Security Management System — the policies, risk treatment process, access controls, incident response procedures, and continuous improvement loop your organization uses to protect information assets. When an AI vendor says they are ISO 27001 certified, it means an accredited certification body audited their ISMS against Annex A controls and issued a three-year certificate with annual surveillance audits. It does not mean the AI models themselves are certified — that is a category mistake, and one that vendor marketing copy frequently encourages. Per the standard's text and the guidance at https://www.iso.org/standard/27001, the certification scope is whatever the organization defined, which is why reading the scope clause matters more than seeing the badge.
**ISO/IEC 27017** is the cloud services extension. It adds 7 cloud-specific controls and provides implementation guidance for 37 existing 27001 controls in a cloud context — things like virtual environment isolation, administrator operational security, and customer-cloud-provider responsibility split. When AWS, Azure, and Google publish 27017 alongside 27001 (see https://aws.amazon.com/compliance/iso-27001-faqs/), they are documenting how the hyperscaler's shared-responsibility model maps to internationally agreed-upon cloud controls. An AI API vendor that holds 27017 has signed up to specific cloud operational hygiene that goes beyond the generic ISMS.
**ISO/IEC 27018** is the PII-in-public-cloud extension. It is built on top of 27002 and adds controls for processing personally identifiable information in a public cloud environment as a PII processor. The control set covers consent, transparency, deletion timelines, and restrictions on PII use for advertising. For AI providers, 27018 matters because user prompts and uploads often contain PII — a provider holding 27018 has audited evidence that they treat that data as a regulated processor would. **OpenAI** at https://trust.openai.com/ and **Anthropic** at https://trust.anthropic.com/ both hold current 27018 attestations.
**ISO/IEC 27701** is the Privacy Information Management System (PIMS) extension. Where 27001 is about security, 27701 is about privacy as a discipline — data subject rights, lawful basis, cross-border transfer documentation, privacy impact assessment processes, and the GDPR/CCPA mapping appendices. An AI vendor with 27701 has built a privacy management system audited to an international standard. This is the certification your DPO actually cares about. Per Google's documentation at https://cloud.google.com/security/compliance/iso-27001 the 27701 scope inherits the underlying 27001 boundary.
**ISO/IEC 42001:2023** is the newest and most relevant. Published in December 2023 at https://www.iso.org/standard/81230.html, it is the world's first AI Management System standard. It defines requirements for an organization to establish, implement, maintain, and continually improve an AIMS — covering AI risk assessment, AI impact assessment (a distinct concept from privacy impact assessment), data governance for AI training and operation, AI system lifecycle management, third-party AI risk, and stakeholder communication. Where 27001 asks 'is your information secure?', 42001 asks 'is your AI development and deployment governed?'. This is the certification that maps most cleanly to EU AI Act obligations for high-risk systems.
The marketing copy to ignore: any vendor claiming their model is ISO certified, any vendor showing an ISO logo without a scope statement and effective date, and any vendor implying that 27001 alone is sufficient evidence of AI governance. It is not. 27001 covers the company's information security program. 42001 covers the AI program. They are complementary, not interchangeable, and in 2026 the gap between vendors who hold both versus only the former is the cleanest signal of AI-governance maturity available to procurement teams.