How MarkHub handles and protects your data

TUNNING GROUP LLC · Data handling & security

What we access, and what we don't

MarkHub reads a defined set of your Amazon seller data — orders, order items, your own listings, pricing/Buy Box, fees and reports — strictly to power the features described on our Features page. MarkHub does not store buyer name, street address, phone number, email or payment information. It temporarily holds limited destination location (city and state/region) attached to an order — used only to show you the geographic distribution of your own sales — for up to 30 days, after which that field is automatically deleted. Where you need full shipping details, MarkHub links you to that order in Seller Central.

Data isolation (multi-tenant)

Every record belongs to one workspace, and every workspace belongs to one account owner. Isolation is enforced in two independent layers: PostgreSQL Row Level Security scoped to the authenticated user, plus an explicit workspace filter in the application query layer. One seller's data is never combined with, benchmarked against, or exposed to another's.

Encryption

In transit: all traffic uses HTTPS/TLS, with HSTS enabled.
At rest: data is stored encrypted (AES-256) by our managed database provider, with keys managed by the provider's Key Management System.
Amazon authorization token: the refresh token that lets MarkHub call Amazon on your behalf is additionally encrypted with AES-256-GCM using a key held outside the database. A database dump without that key does not expose the token. We never see or store your Amazon password.

Data retention & deletion

Any limited location data we hold on an order (city/state only) is automatically erased 30 days after the order, in line with Amazon's Data Protection Policy. You can disconnect MarkHub from your Amazon account at any time from Seller Central under Apps & Services; revoking there immediately stops MarkHub from reaching your account. On account closure or on request, your workspace and all data in it are deleted and the stored Amazon token is revoked.

Access & secrets

Application secrets are held server-side only and are never exposed to the browser; no public client variable carries a secret. Secrets live in encrypted environment variables, never in source control. Access to production data is limited to authorized operators of TUNNING GROUP LLC on a need-to-know basis.

Network & application protection

No self-managed database or file server is exposed to the public internet — the database is a managed instance, the application runs on managed serverless hosting, and background workers run on managed infrastructure, all accessed over TLS. Security headers (HSTS with preload, nosniff, frame-ancestors 'none', strict Referrer-Policy) are enforced at the edge, API responses are set to no-store, and outbound fetches are protected against SSRF (private and metadata IP ranges are blocked and every redirect is re-validated). Expensive endpoints are rate-limited.

Sub-processors

MarkHub relies on established sub-processors to operate: authentication (Clerk), payments (Stripe — billing details only, never Amazon Information), application hosting (Vercel), background workers (Railway) and database (Supabase). Each processes only the data needed for its function, on our instruction, under its own security and confidentiality terms.

Your controls

Connect and disconnect from Seller Central at any time; export your data; and contact us at support@usemarkhub.com for any data request. See also our Privacy Policy.