# Privacy Filter

> **TL;DR.** Privacy Filter is an open-weight, on-device model for detecting and redacting personally identifiable information (PII) from unstructured text.

- **Category:** AI / Privacy / Data Infrastructure
- **Stage:** validating
- **Age:** 55 days
- **Origin date:** 2026-04-22
- **First detected:** 2026-04-24
- **Canonical URL:** https://earlyterms.com/term/privacy-filter
- **Sources:** 8 primary URLs

## Definition

Privacy Filter is an open-weight, on-device model for detecting and redacting personally identifiable information (PII) from unstructured text. It runs locally — no data leaves the machine — making it a preprocessing layer before feeding documents or prompts to cloud LLMs.

OpenAI released [Privacy Filter on April 22, 2026](https://openai.com/index/introducing-openai-privacy-filter/) under Apache 2.0 on [GitHub](https://github.com/openai/privacy-filter) and Hugging Face. The 1.5B-parameter bidirectional model (only 50M active) achieves 97.43% F1 on PII-Masking-300k with a 128,000-token context window, catching eight entity types: names, addresses, emails, phone numbers, URLs, dates, account numbers, and secrets like API keys.

## Example

A legal team feeds merger-related emails into an AI summarization workflow. Privacy Filter runs first, locally, replacing all attorney names and case numbers with placeholders like [PRIVATE_PERSON] and [ACCOUNT_NUMBER] before the text reaches the cloud LLM. The clean output goes to OpenAI's API; the raw data never leaves the firm's server.

## Analogy

Think of it as a bouncer for your text — it strips IDs before the crowd enters the LLM.

## Why it's emerging now

OpenAI's April 22, 2026 open-source release of Privacy Filter directly addressed the most common enterprise AI risk: employees pasting PII into cloud LLMs. A bidirectional 1.5B-param model that runs on a laptop, logs nothing, and strips PII before it reaches any API closed that loop at the infrastructure level.

## Related terms

- *related:* managed-agents
- *related:* openai-agents-sdk
- *related:* context-engineering
- *related:* vibe-coding
- *related:* model-context-protocol
- *parent:* PII redaction
- *parent:* data masking
- *competitor:* Microsoft Presidio
- *competitor:* AWS Comprehend
- *related:* on-device AI
- *related:* GDPR compliance tooling
- *related:* agent-harness

## Sources

1. [OpenAI — Introducing OpenAI Privacy Filter (official blog, Apr 22, 2026)](https://openai.com/index/introducing-openai-privacy-filter/)
2. [GitHub — openai/privacy-filter repo (1.2k stars, Apache 2.0)](https://github.com/openai/privacy-filter)
3. [Hugging Face — openai/privacy-filter model card](https://huggingface.co/openai/privacy-filter)
4. [VentureBeat — OpenAI launches Privacy Filter, on-device data sanitization model (Apr 22, 2026)](https://venturebeat.com/data/openai-launches-privacy-filter-an-open-source-on-device-data-sanitization-model-that-removes-personal-information-from-enterprise-datasets/)
5. [Bloomberg Law — OpenAI Releases Privacy Filter Model to Redact Sensitive Data (Apr 22, 2026)](https://news.bloomberglaw.com/privacy-and-data-security/openai-releases-privacy-filter-model-to-redact-sensitive-data)
6. [Decrypt — OpenAI Just Open-Sourced a Tool That Scrubs Your Secrets Before ChatGPT Ever Sees Them](https://decrypt.co/365139/openai-privacy-filter-open-source-pii-masking-model)
7. [Help Net Security — OpenAI tackles a bad habit people have when interacting with AI (Apr 23, 2026)](https://www.helpnetsecurity.com/2026/04/23/openai-privacy-filter-personally-identifiable-information/)
8. [Hacker News — OpenAI model for masking PII in text (60 pts, Apr 23, 2026)](https://news.ycombinator.com/item?id=47870901)

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_Generated by EarlyTerms · https://earlyterms.com/term/privacy-filter_