§ 1 What this list is
This page lists the Sub-processors engaged by Halton Labs Ltd ("Halton Labs") to provide Halton Meter Cloud ("the Service") as at the effective date above. It is incorporated by reference into the Terms of Service and the Data Processing Addendum, and reflects Annex 3 of the DPA. Where there is any discrepancy between this page and Annex 3, Annex 3 controls.
A "Sub-processor" is a third party engaged by Halton Labs that processes Customer Personal Data on Halton Labs' behalf to provide the Service. Recipients that are not engaged by Halton Labs — including the Customer's own LLM providers (see § 7) — are not Sub-processors and are not listed here.
§ 2 Change notification
Halton Labs will give Customers at least 14 days' prior notice of the addition or replacement of any Sub-processor. Notice will be given by email to the workspace billing contact and by an update to this page. A Customer that reasonably objects on data-protection grounds may terminate the affected Service for convenience as described in § 8 of the DPA; this is the Customer's exclusive remedy for an objection to a Sub-processor change.
Material changes to this page are also reflected in the changelog at the foot of the page so that procurement teams can diff revisions over time.
§ 3 Infrastructure
- Amazon Web Services EMEA SARL — primary
hosting, database (RDS PostgreSQL) and object storage (S3) for
all Cloud workspace data, including any Stored Content opted in
under the content opt-in.
Location of processing: United Kingdom (eu-west-2, London).
Transfer mechanism: no UK cross-border transfer in the ordinary course; the AWS GDPR Data Processing Addendum applies.
Data seen: all categories listed in Annex 1 of the DPA. - Vercel Inc. — edge hosting for the dashboard at
app.haltonmeter.com (static assets and Server Components).
Location of processing: United States (primary), with request termination at the nearest Vercel edge.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses.
Data seen: request metadata (IP, user agent, path) necessary to route and render the dashboard. No Customer Personal Data is stored at rest at Vercel; Stored Content never transits Vercel. - Cloudflare, Inc. — DNS and CDN for the marketing
site at cloud.haltonmeter.com.
Location of processing: global edge.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses.
Data seen: request metadata for static marketing pages only. No workspace data. No Stored Content.
§ 4 Authentication and billing
- Clerk, Inc. — authentication (sign-in, sign-up,
session management) and billing (Clerk Billing). Clerk uses
Stripe upstream as the card-network processor; raw card numbers
go directly from the data subject's browser to Stripe via Clerk's
hosted billing interface — they do not pass through Halton Labs.
Location of processing: United States.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses (or the IDTA where Clerk's published terms provide for it).
Data seen: account email, display name, plan and billing reference. No usage metadata. No Stored Content. - Svix Inc. — webhook delivery for events emitted
by Clerk (e.g. subscription state changes).
Location of processing: United States.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses.
Data seen: event payloads that may include account identifiers and plan metadata. No usage metadata. No Stored Content.
§ 5 Email
- Resend, Inc. — transactional email (scheduled
reports, workspace invitations, billing notifications, security
notices). Sender domain:
haltonmeter.com, verified with DKIM and SPF.
Location of processing: United States.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses.
Data seen: recipient email address, recipient display name (where included), email subject and body. No prompt or response content is sent to Resend.
§ 6 Error telemetry
- Sentry (Functional Software, Inc.) — error
reporting from the dashboard and API.
Location of processing: United States.
Transfer mechanism: UK Addendum to the EU Commission Standard Contractual Clauses.
Data seen: redacted error payloads (stack traces, request paths, user agent), with Customer Personal Data scrubbed before transmission. No prompt or response content is sent to Sentry under any configuration.
§ 7 LLM providers are not Halton Labs sub-processors
The Customer's LLM provider API keys live on the Customer's own developer machines, and the Halton Meter daemon forwards LLM API traffic directly from those machines to the relevant provider (Anthropic, OpenAI, Google, Groq, and so on). Those provider API calls do not transit Halton Meter Cloud.
Each LLM provider is therefore the Customer's own processor under the Customer's direct contract with that provider, and is not a sub-processor of Halton Labs under the DPA. The DPA's sub-processor flow-down obligations do not apply to those providers.
CL Changelog
- 28 May 2026 — initial draft. Includes AWS, Vercel, Cloudflare, Clerk, Svix, Resend, Sentry. Awaiting solicitor review before publication.