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PHI · HEALTHCARE AI · PRIVACY & COMPLIANCE

Protect patient privacy in every clinical note.

PHI identifies and de-identifies protected health information in unstructured clinical text through one automated pipeline - so your richest clinical data is safe to use across research, AI, analytics and partnerships.

~80%
of clinical data lives in unstructured free text
27
fine-grained PHI entity types detected, 30 obfuscated
16 / 18
HIPAA Safe Harbor identifiers addressed in text
95%+
validated recall targets where it matters most
THE TWO-STAGE PIPELINE

Two coordinated stages: identify, then de-identify

PHI is built as two coordinated stages, deliberately separated so each can be scaled and governed independently - identification is the only GPU-bound component.

The result reads like a real note. Surrogates let PHI “hide in plain sight,” keeping the text natural and analyzable while the patient behind it stays protected.

  • Identify - a fine-tuned clinical-language model (~1.7B-parameter Qwen3 family, LoRA/QLoRA) tags every PHI element in narrative context, returning the note plus typed entities and character offsets.

  • De-identify - a second stage redacts each identifier or replaces it with a realistic, format-preserving surrogate - configurable per entity type and consistent within a document.

Original note

Patient John A. Smith, MRN 4471829, seen 03/14/2024 by Dr. Alvarez at Mercy General.

De-identified note

Patient Robert Lee, MRN 8830142, seen 06/22/2024 by Dr. Nguyen at Lakeside Health.

Every identifier is replaced with a realistic, format-preserving surrogate - the note stays natural and analyzable.
THE PROBLEM

Hidden risk inside clinical text

Roughly 80% of clinical data lives in unstructured free text - the progress notes, radiology reports and narratives where the richest clinical signal sits. It is also where PHI is hardest to control: names, dates, MRNs, addresses and other identifiers are scattered through prose, easy to miss, and costly to remove by hand. Under HIPAA, a single missed identifier is a breach - and that risk keeps the most valuable clinical data sealed off from research, analytics and AI.

Why legacy de-identification tools fall short

  • PHI is buried in the narrative - identifiers woven into sentences, not tidy fields, so they are easy to overlook.

  • Manual review does not scale - human redaction is expensive, inconsistent, and can’t keep pace with millions of documents.

  • Legacy systems lack context - rule-based patterns and lookup tables miss nuance and mislabel identifiers.

  • Compliance exposure is binary - one leaked identifier is a breach, so organizations lock data down and block legitimate use.

Where PHI Hides - and Where Legacy Tools Stop
A clinical record
Structured fields (~20%)
Tables · codes · demographics
Unstructured narrative (~80%)
Progress notes · radiology reports · summaries
Legacy rule-based tools
Stop at the structured fields
PHI
Reasons over the narrative where identifiers hide
Legacy tools handle the structured fields; PHI reasons over the unstructured narrative where identifiers hide.
HOW IT WORKS

A clean, composable de-identification pipeline

A clinical note flows through a clean, composable pipeline before emerging as safe, shareable text. The two stages are exposed as a simple contract: an entity-extraction call returns the note and its typed entities; an obfuscation call takes the note plus entities and returns the masked content.

  • Identify - the SLM tags typed entities with character offsets, in context.

  • De-identify - redact or replace each entity using a type-specific strategy.

  • Configurable - per entity type: realistic surrogate, generic redaction, typed redaction, or untouched.

  • Document-consistent - the same original value maps to the same surrogate every time, with casing preserved.

PHI De-Identification Pipeline
Clinical note
Unstructured input
Identify
SLM tags typed PHI entities + offsets
De-identify
Redact / realistic surrogate
Safe output
Shareable, analyzable text
Simple two-call contract
Entity-extraction call → note + typed entities · Obfuscation call → masked content
A note flows in, PHI is identified with typed entities, then redacted or replaced - safe output flows out.
COVERAGE

HIPAA Safe Harbor alignment

PHI detects 27 fine-grained entity types and obfuscates 30 in total. 16 of the 18 Safe Harbor identifiers are addressable in unstructured text; the two excluded - biometric identifiers and full-face photographs - are non-text by design.

Safe Harbor identifier coverage

Identifier groupRepresentative entitiesIn scope
NamesPatient, provider, other namesYes
Geography (sub-state)Street, city/state, ZIP, country, facilityYes
Dates & age over 89DOB, death, service dates, age 90+Yes
Telephone & faxPhone numbers (fax handled as phone)Yes
Email / Web & networkEmail, URLs, IP addressesYes
Record / account numbersMRN, account number, health-plan IDYes
Other identifiersSSN, license, device, vehicle, ID/codesYes
Biometric identifiers- (non-text)No
Full-face photographs- (non-text)No

Surrogate strategy by type

PHI typeSurrogate strategy
NamesRandom draw from curated name lists
GeographyRandom draw from curated place / facility lists
ZIP codesFormat-preserving numeric substitution
DatesDate shifting, optional truncate-to-year
Identifiers (MRN, account, SSN, device…)Character/digit-class substitution preserving length & format
Phone / faxFormat-preserving number substitution
Email, URL, IPType-appropriate synthetic value
VALIDATED PERFORMANCE

Recall you can defend - measured the conservative way

Accuracy is measured as document-level All-or-Nothing recall - the share of documents in which every instance of an identifier type is caught - the conservative bar that matters for compliance. Benchmarked on radiology notes across eight imaging modalities, outperforming the Amazon Macie baseline.

Document-level recall (radiology-note benchmarks)

PHI categoryDocument-level recallNotes
Date of birthUp to 100%Highest on PET, PET/CT, ultrasound
MRN & patient names~98%Consistent across modalities
Ages, dates & addresses96–97%Mid-to-high 90s overall
Patient location (quasi-ID)~79%Hardest category; active focus area

Throughput & latency

StageThroughput (min config)p95 latency
PHI identification~100 requests / minute~10 seconds
Obfuscation~2,500 requests / minute~100 milliseconds
Recall figures are validated targets from radiology-note benchmarks, not guarantees. Per-note-type validation - document-level scoring at 95% confidence - is part of onboarding, so the evidence is specific to your notes.
WHY PHI IS DIFFERENT

Built for evidence, not generic claims

  • Accuracy, tuned to you - fine-tuned on your own notes and note types to reach 95%+ recall where it matters most.

  • Compliance you can prove - document-level scoring with statistical validation at 95% confidence, per note type - defensible evidence, not a generic claim.

  • Deploy your way - managed SaaS or fully on-premise; PHI never has to leave your environment.

  • Utility preserved - type-specific, format-preserving, document-consistent surrogates keep de-identified data usable for research and analytics.

SECURITY & DATA CONTROL

Your notes never leave your control

PHI handles protected health information, so the architecture is built to keep that data locked down at every layer - from where the notes are processed to how the model itself is reached.

  • PHI stays in your environment - on-premise, notes are processed entirely inside your own infrastructure; nothing is sent out for inference.

  • The model is not directly exposed - clients interact only with the orchestrating API; the inference server is bound to localhost and isolated.

  • Hardened containers - distroless-style images limit shell access; the model server fails closed if it detects external exposure.

  • Encryption & mediated control plane - TLS in transit; an egress proxy mediates control-plane communication.

WHAT DE-IDENTIFICATION UNLOCKS

De-identify once - use the data everywhere

Once notes are reliably de-identified, the same dataset can safely serve many teams at once - health systems, researchers, payers, life sciences and health-tech vendors.

Research & real-world evidence

Share real patient data for studies, safely.

AI & model development

Train and validate models on real notes, compliantly.

Analytics & population health

Surface trends and outcomes without PHI exposure.

Data sharing & partnerships

Exchange data with vendors, registries and collaborators.

Non-production environments

Realistic data for testing, demos and QA with no live PHI.

Data products & secondary use

Build and license de-identified datasets.

De-identify once. Put your clinical data to work.

Book a demo and we’ll show PHI identifying and de-identifying on a sample of your own clinical notes.

Request a demo