pydantic

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pydantic declares 17 subprocessors in its subprocessor list, which we last checked on Nov 11, 2026 (evidence). They include Amazon Web Services, Google Cloud and OpenAI. No published changes since we first read it on Nov 5, 2026. 4 tracked vendors name pydantic as a subprocessor, including Oneleet, Firmable and Meridian AI.

Subprocessors CSV · Atom DORA draft CSV what's this? · 

17 third parties.

NamePurposeLocationListed since
Amazon Web Services Cloud hosting and email deliveryUS; EU
Anthropic, PBC AIUS (storage); global (Gateway inference)
Clay, Inc. Sales enrichment and account managementUS
Cloudflare, Inc. Content delivery and traffic routingUS
Customer.io, Inc. Marketing and lifecycle emailsEU
Day AI, Inc. Customer relationship management and interaction historyUS
Devenue Inc. (Reo.Dev) Developer intent and account intelligenceUS (hosting)
Google LLC AIEmail, documents, video conferencing, and AI assistance (Gemini)US
Google Cloud Platform (Vertex AI) AICloud hostingUS; EU; US, EU (Logfire AI); global (Gateway)
HubSpot, Inc. Customer relationship managementEU (hosting); US (additional processing)
Metronome Holdings Inc. Usage-based billing (Gateway enabled)US
OpenAI AIUS; global (Gateway)
PagerDuty, Inc. Incident management and alertingEU
PostHog Inc. Product analytics and submitted sales inquiry contact dataEU
Pylon, Inc. Customer supportUS
Slack Technologies, LLC Messaging and file sharingUS
Stripe, Inc. Payment processingUS

Web TechnologiesCSV · Atom

pydantic's homepage made 39 requests to 4 domains, and 1 service controlled by another company.

Advertising (1): Google Cloud

1 third party by category: Advertising 1

Third parties 1 · 7 requests
Google Cloudsubprocessor DoubleClick Floodlight Google Analytics Google Tag Manager 18% of the page's requests 7
First party 1 · 32 requests
pydantic Astro Cloudflare HSTS HTTP/3 Open Graph PWA PostHog Priority Hints RSS 82% of the page's requests 32

Subprocessor of (4)CSV · Atom

4 companies
  • Firmable firmable.ai Logging and Telemetry
  • Meridian AI meridian-ai.com AI tracing and observability (Logfire); Pydantic Logfire traces Meridian's AI research agent to monitor and debug its behavior. Customer data processed: LLM prompts and responses.
  • Oneleet oneleet.com AI Observability Platform
  • Seekr seekr.com Data Observability

Incidents reported by pydantic's subprocessorsCSV · Atom

68 reported incidents in the last 30 days, by 8 of the vendors pydantic lists as subprocessors.

A subprocessor list names a company, not the service an incident touched. This does not show that pydantic was involved.

DateCompanyIncidentImpactLasted
OpenAIUnable to start new Workspace Agent runs criticalongoing
OpenAIElevated errors affecting logins, sign-ups, and ChatGPT features minor8 min
PylonSlack Integration Connection Issues major3 h 13 min
AnthropicElevated errors on Fable 52 and Mythos 52 no impact stated1 min
HubSpotSome HubSpot tools may be unavailable for some users no impact stated51 min
OpenAIIncorrect cost data in Costs API exports no impact stated2 h 20 min
OpenAIElevated Errors On API minor42 min
OpenAIElevated ChatGPT Conversation Errors minor52 min
Day AIData delays in some parts of the app + MCP major—
OpenAIElevated errors with image generation minor1 h 49 min
AnthropicDegraded performance for Claude Fable 5.1 minor26 min
Customer.ioCustomers are Unable to add new Email Sending Domains major30 min
OpenAIElevated error rates with some U.S. business Mastercards no impact stated3 days
PylonDelay in Analytics Data minor3 h 16 min
OpenAIChatGPT Work and Dots Errors minor13 h 6 min
OpenAIElevated error rates across paid ChatGPT plans minor1 h 54 min
PylonInbound Email Delays minor1 h 17 min
OpenAIFile upload errors in ChatGPT minor4 h 52 min
HubSpotHubSpot is experiencing issues no impact stated22 min
StripeElevated Instant Payouts failures no impact stated2 h 5 min
OpenAIElevated errors with search in Dots, ChatGPT Work, and certain ChatGPT thinking experiences minor1 h 35 min
OpenAIElevated errors for GPT Image 2 API image edits minor4 h 1 min
StripeElevated Issuing errors from 17:13 - 20:41 UTC minor4 h 36 min
AnthropicElevated errors affecting the Google Calendar connector minor3 h 46 min
AnthropicElevated errors affecting the Gmail connector minor1 h 48 min

And 43 more. All of them: CSV · Who is around them.

ChangesCSV · Atom

See the list as we read it on any date: Time machine

None since tracking began.

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