Solution

HIPAA-ready AI architecture — not HIPAA compliance

Reducing PHI exposure before it reaches an LLM API.

Privian is not HIPAA certified and does not sign a business associate agreement. What it does is detect and mask identifiers before a prompt leaves your systems, which is one architectural input into a compliance programme you and your counsel own — not a substitute for one.

Can you use an LLM API with PHI?

Only inside a compliance programme you control: either sign a business associate agreement with every processor that will touch the PHI, or remove enough identifying detail before the data leaves your boundary that it meets HIPAA's de-identification standard. A vendor's technical controls can support either path; they do not complete either one on their own.

Plain statement

What Privian is — and is not

Privian is not HIPAA certified and does not sign a BAA. This page describes HIPAA-ready architecture: technical controls that can reduce how much PHI reaches a model provider. It is not a compliance product, and using it does not make your application HIPAA compliant.

HIPAA compliance is a property of a covered entity or business associate and its full administrative, physical and technical safeguards programme — risk analysis, workforce training, access controls, breach procedures, and signed agreements with every business associate in the chain. No single vendor component can hold that property on its behalf. A privacy layer can change whether PHI reaches a given processor at all; it cannot certify your organization, and it cannot stand in for a BAA where one is legally required.

Summary

The short version

What is the problem?

Clinical notes, intake forms, support tickets, scheduling context and billing references routinely contain PHI, and healthcare-adjacent SaaS features increasingly send that context to LLM APIs without a BAA covering the model provider.

How is it solved?

Reduce PHI reaching a provider by detecting and masking identifiers before the call, or route PHI-bearing flows through processors under a signed BAA — these are two different paths, not one control that satisfies both.

When should this approach be used?

When you are evaluating whether an AI feature can touch PHI at all, and you need to separate 'what architecture can reduce' from 'what only a compliance programme and legal agreements can establish'.

What are the limitations?

Best-effort masking over a fixed entity set does not meet the Safe Harbor de-identification standard, does not constitute an Expert Determination, and does not replace a BAA. Privian offers neither certification nor a BAA today.

Problem

PHI exposure in healthcare-adjacent SaaS

Products that are not themselves clinical systems still routinely handle PHI once an AI feature is added: a summarizer condenses a clinical note, an intake form's free-text field is passed to a model for triage, a support ticket references a patient's diagnosis, a scheduling assistant reads an appointment tied to a treatment type, or a billing workflow includes a claim number next to a patient name. None of these look like "health records" in the product's data model — they are ordinary text fields that happen to contain individually identifiable health information.

The result is that PHI can reach a model provider's API through the same incidental path as any other customer data — because a feature was built without anyone asking whether the field could contain health information at all.

Safe Harbor coverage

What Privian's detector does and does not cover

HIPAA's Safe Harbor de-identification method lists 18 categories of identifiers that must all be removed for data to qualify. Privian's supported entity set overlaps with some of these categories and does not currently cover several others — this gap is the reason masking is a technical control, not a de-identification determination.

  • Names — partially covered

    Person names are in Privian's supported entity set on a best-effort basis. Safe Harbor requires removal of all names, which best-effort NLP detection cannot guarantee.

  • Geographic subdivisions smaller than a state — NOT covered

    Street addresses, cities, precise geographic detail and most ZIP code rules are not part of the supported entity set.

  • All elements of dates (except year) — NOT covered

    Birth dates, admission/discharge dates and dates directly related to an individual are not detected or masked.

  • Phone numbers — covered

    Phone numbers are in the supported entity set.

  • Email addresses — covered

    Email addresses are in the supported entity set.

  • Social Security numbers — partially covered

    US SSN is supported. Other national identifiers beyond US SSN and Canadian SIN are not.

  • Medical record numbers — NOT covered

    MRNs are not a supported entity type.

  • Health plan beneficiary numbers — NOT covered

    Insurance/health plan member identifiers are not a supported entity type.

  • Account numbers — NOT covered as a distinct category

    Privian does not have a general 'account number' detector; only specific formats such as card numbers and IBANs are covered.

  • Certificate/license numbers — NOT covered

    Not a supported entity type.

  • Vehicle identifiers — NOT covered

    Not a supported entity type.

  • Device identifiers and serial numbers — NOT covered

    Medical device identifiers are not a supported entity type.

  • URLs and IP addresses — IP addresses covered, URLs not

    IP addresses are supported; web URLs are not a distinct detected category.

  • Biometric identifiers — NOT covered

    Not applicable to a text-based prompt gateway.

  • Full-face photographs and comparable images — NOT covered

    Privian processes text prompts; image content is out of scope entirely.

  • Any other unique identifying number, characteristic or code — NOT reliably covered

    This catch-all category cannot be satisfied by a fixed, best-effort entity list by definition.

The full current entity catalog is listed on the PII masking page. Achieving Safe Harbor requires all 18 categories to be addressed; Privian's detector was not built against that checklist and should not be treated as satisfying it.

Framework

Two paths to reducing PHI exposure

Framework

Choose the path deliberately, per data flow

  1. 01

    Path A — Keep PHI in scope, sign BAAs

    PHI stays PHI throughout the flow. Every processor that touches it — including the model provider and any gateway in between — must be covered by a signed business associate agreement, and your full HIPAA programme applies end to end.

  2. 02

    Path B — Reduce what leaves the boundary

    Minimize or de-identify before egress so that materially less PHI (ideally none, under a recognized de-identification standard) reaches any processor. This narrows what needs a BAA, but the de-identification itself has to meet Safe Harbor or Expert Determination — not just 'masking most of it'.

Privian's controls are relevant to Path B as one input: reducing identifying content in the prompt. They do not implement Path A — Privian does not sign a BAA — and they do not by themselves complete Path B's de-identification standard.

Provenance

About HIPAA-specific claims

Control 1

Detecting PHI-adjacent identifiers before transmission

Privian scans the assembled prompt for its supported entity set on each request, with no cross-request state: names, emails, phone numbers, IP addresses, credit cards, IBAN, US SSN, Canadian SIN, JWTs, provider API keys, GitHub tokens, AWS keys and env-style assignments. As shown above, this set does not cover several categories HIPAA treats as identifiers — dates, medical record numbers, health plan beneficiary numbers, device identifiers and images among them.

Control 2

Masking before the provider call

Detected values are replaced with deterministic, type-aware placeholders — PERSON_1, EMAIL_2 — for the duration of the request. The masked prompt keeps its shape so the model can still reason about relationships, but the supported identifiers do not cross the boundary as plain text.

Control 3

In-memory rehydration

The mapping between placeholders and original values is held in memory for the life of the request only. Placeholders in the model's response are replaced back with the original values before your application sees the reply, and the mapping is then discarded. See rehydration for the mechanics.

Control 4

Data path and retention

Every request through Privian follows one describable path: detection and masking, forwarding to the model provider under your own BYOK credentials, and rehydration of the response. Privian does not persist raw prompts or responses; only structural counters are retained for billing and observability. The full hop-by-hop description is on the data path page. None of this changes whether the model provider itself is under a BAA — that is a separate agreement you would need directly with that provider if PHI reaches it.

Architecture

Implementation architecture

  1. 1

    Application Your code calls the OpenAI Chat Completions-compatible shape, with the base URL pointed at Privian and a Privian gateway key.

  2. 2

    Privian privacy layer The assembled prompt is scanned, supported entities are replaced with deterministic placeholders, and the request-scoped mapping is held in memory.

  3. 3

    Model provider The masked request is forwarded to the provider addressed as provider/model, using your own encrypted BYOK credentials.

  4. 4

    Privian rehydration Placeholders in the response are replaced with the original values from the in-memory mapping, which is then discarded.

  5. 5

    Application Your code receives a response containing real values — no placeholder handling required downstream.

One endpoint, one round trip. Detection, masking and rehydration happen in a single in-memory pass; nothing is queued or persisted between hops.

Compliance review

Questions your compliance reviewer will ask

Framework

Have honest answers ready before the review, not during it

  1. 01

    Is this vendor a business associate under a signed BAA?

    No, if the vendor is Privian. If PHI reaches Privian or any downstream model provider, you need a BAA with each of them directly, or PHI should not reach that flow.

  2. 02

    Does the vendor claim HIPAA compliance or certification?

    No. Treat any product claiming to be 'HIPAA compliant AI' with the same scrutiny — compliance is not a certifiable product property.

  3. 03

    Has the data been de-identified to a recognized standard?

    Only if you or a qualified expert have determined it meets Safe Harbor or Expert Determination — not simply because a masking tool ran over it.

  4. 04

    What identifier categories are NOT covered by the masking layer?

    Dates, medical record numbers, health plan beneficiary numbers, device identifiers, biometrics and images, among others — see the coverage table above.

  5. 05

    What is retained, and by whom, at each hop?

    Answerable per hop via the data path; your own logging and analytics are usually the largest retained copy and are entirely under your control.

Fit

When this architecture is useful — and when it isn't

Useful when

  • You want to reduce incidental PHI exposure in non-clinical AI features (support, scheduling, billing text)
  • You are deciding, per data flow, whether PHI needs to reach a model at all
  • You need one enforced egress control while your compliance programme is separately being built
  • You want a documented, hop-by-hop data path to show a reviewer

Not a fit when

  • You need a signed BAA with the party processing PHI — Privian does not offer one
  • You need a certified HIPAA compliant product to satisfy an auditor's checklist
  • Your data flow requires a formal Safe Harbor or Expert Determination de-identification
  • Your PHI includes dates, MRNs, device IDs, images or other identifiers outside the supported entity set

Scope

What this does NOT solve

FAQ

Frequently asked questions

Can you use an LLM API with PHI?
Only within a compliance programme you control — with a signed business associate agreement covering every processor that touches the PHI, or by removing enough identifying detail before egress that what remains is no longer PHI under HIPAA's de-identification standards. No vendor product makes either path automatic.
Is Privian HIPAA compliant?
No, and the question is mis-framed. HIPAA compliance describes a covered entity's or business associate's full administrative, physical and technical safeguards programme — not a property a single vendor component can hold on its own. Privian does not claim certification and does not sign BAAs.
Does Privian sign a BAA?
No. Privian does not currently offer a business associate agreement. If your use case requires PHI to reach a downstream processor under HIPAA, you need a BAA with that processor directly — Privian is not a substitute for one.
What is a HIPAA compliant LLM?
Strictly, there is no such thing as a certified 'HIPAA compliant model' — compliance attaches to the covered entity's use of a system under a BAA and a documented programme, not to the model itself. Vendors that describe a product as 'HIPAA compliant AI' are usually describing BAA availability plus their own safeguards, which you still have to verify and operationalize.
Does masking PHI satisfy HIPAA de-identification?
Not by itself. HHS recognizes two de-identification methods: Safe Harbor, which requires removing 18 specific identifier categories, and Expert Determination, which requires a qualified expert's statistical assessment. Best-effort detection over a fixed entity set is a useful technical control but is not, on its own, a Safe Harbor determination or an Expert Determination.
What counts as PHI in a support ticket or chat transcript?
Any individually identifiable health information linked to a person — which can include a name next to a diagnosis, a scheduling note referencing a treatment, or a billing reference tied to a claim. PHI often appears in free text that was never tagged as a health record, which is why it can reach an LLM prompt without anyone deciding to send health data.
Can de-identified data still leave the HIPAA boundary safely?
Data that genuinely meets the Safe Harbor or Expert Determination standard is no longer PHI and HIPAA's restrictions on it no longer apply. Reaching that standard is a determination you or a qualified expert make about the specific dataset — a masking layer can reduce identifying content but does not itself make that determination.
What should a healthcare-adjacent SaaS company do instead of assuming compliance?
Decide, per data flow, whether PHI needs to reach the model at all. Where it does, put a BAA in place with every processor in that path. Where it doesn't, minimize what leaves the boundary and treat any residual identifiers as still in scope for your programme rather than assuming a masking tool has resolved the question.
Should we consult anyone before relying on this architecture?
Yes. This page describes technical architecture, not legal advice. Confirm your classification of PHI, your de-identification approach and your processor agreements with your own counsel or compliance officer before treating any configuration as sufficient.

Related

Related reading

This page is provided for architectural and educational purposes only and is not legal advice. Whether your specific data flows require a BAA, whether your de-identification approach meets HIPAA standards, and whether Privian is an appropriate component of your programme are questions for your own counsel or compliance officer.

Plans & pricing

Pricing for reducing PHI exposure before egress

BYOK, zero retention and masking before the provider call. Not a compliance certification and not a substitute for a BAA. Beta plans may change as the product matures.