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Cross-Platform PII: Office & LibreOffice

How organizations with mixed Microsoft Office and LibreOffice environments maintain consistent PII anonymization using anonym.

March 10, 20267 minute read
LibreOffice extensioncross-platform anonymizationmixed office environmentdocument redaction consistencyenterprise PII

The Mixed Office Problem

Most firms run more than one office suite. Legal teams use Word. Engineers on Linux use LibreOffice. Mergers bring teams with different software. Government work adds ODF and OOXML file formats.

This mix creates a PII risk. One tool finds a name in Word. A different tool misses it in Writer. Thresholds vary. Output formats differ.

That gap is a compliance risk. GDPR Article 32 requires "appropriate technical measures" for data protection. If two suites give two results on the same file, that is not consistently appropriate. The standard is not met.

One Engine, Two Suites

anonym.legal has extensions for both suites:

  • Office Add-in — for Word, Excel, and PowerPoint
  • LibreOffice Extension — for Writer, Calc, and Impress

Both connect to the same backend. They share:

  • 285+ entity types
  • Hybrid detection (regex + spaCy NLP)
  • 48 languages
  • 5 anonymization methods
  • Confidence scoring (regex: 1.0, NLP: 0.85+)

Run the same text in Word or Writer. The result is identical.

Shared Presets Stop Drift

Configuration drift is a silent risk. It happens with no one noticing. Team A sets Word to detect 12 entity types with Replace. Team B sets LibreOffice to detect 8 types with Redact. Same file. Different output.

Preset sync in anonym.legal fixes this:

  1. Create a preset in any platform — web app, Desktop App, Office Add-in, or LibreOffice Extension
  2. The preset syncs to all platforms within 5 minutes
  3. Every user applies the same settings

A preset stores which entity types to detect, the method per type, confidence thresholds, and custom definitions.

Encryption Key Portability

Teams using the Encrypt method (AES-256-GCM) can reverse anonymization to restore the original text. For this to work, keys must be available on all platforms. A file encrypted in Word must be decryptable in the web app or LibreOffice Extension.

anonym.legal uses ZK-wrapped key sync:

  • Keys are wrapped with XChaCha20-Poly1305 using a key derived from your password
  • Wrapped keys sync to the server
  • Your password never leaves your device
  • A server breach cannot expose your keys

Law Firm Workflow: Mixed Suite, One Result

A mid-size law firm takes in files from many sources:

File types:

  • Client contracts in Word (.docx)
  • Court filings as PDF, turned to text
  • Internal memos in LibreOffice Writer (.odt) from Linux desks
  • Spreadsheets as Excel (.xlsx) and Calc (.ods)

How it works:

  1. Senior partner creates a "Client Matter" preset — replace names, mask dates, redact SSNs, encrypt emails
  2. Preset syncs to all platforms
  3. Associate A opens a Word file. Applies preset via Office Add-in.
  4. Associate B opens a Writer file. Applies the same preset via LibreOffice Extension.
  5. Paralegal runs the preset on a Calc file.
  6. All three use the same detection and output settings.

For a GDPR audit, the firm can show:

  • One preset applied across all file types
  • The same entity detection regardless of format
  • The same output methods throughout
  • Keys managed with zero-knowledge security

Enterprise Deployment

FactorOffice Add-inLibreOffice Extension
DeploymentMicrosoft 365 admin center.oxt file distribution
UpdatesAuto-update via manifestManual .oxt replacement
User managementAzure AD integrationanonym.legal accounts
PlatformWindows, Mac, Web, iPadWindows, macOS, Linux
LicensingMicrosoft 365 requiredFree (LibreOffice)

For mixed environments, deploy both. Office Add-in goes on Microsoft 365 desks. LibreOffice Extension goes on Linux and open-source desks. Shared presets and keys keep the behavior consistent.

Regulatory Consistency

Regulators do not accept "we used different tools" as a reason for gaps in anonymization. If a DSAR response redacts a name in the Word file but misses it in the LibreOffice file, that is a gap. It is a compliance failure.

One detection engine across all file types removes this risk. The algorithm does not change based on the client app. It runs server-side the same way for every request. See the security and compliance page and legal conformance docs for details.

Get Started

  1. Download LibreOffice Extension — for Writer, Calc, Impress
  2. Install Office Add-in — for Word, Excel, PowerPoint
  3. Create a preset in the web app — it syncs to both platforms

One account. One preset. One result.

Sources

  • GDPR Article 32 — appropriate technical measures for consistent data protection
  • anonym.legal cross-device sync docs — preset and key portability (/docs/libreoffice)
  • anonym.legal PII Detection Testing — 95.5% accuracy, identical across all platforms

Ready to protect your data?

Start anonymizing PII with 285+ entity types across 48 languages.

About this page

We update this page when our platform or the law changes.

Read our founder note for how we work.

Each change shows up in the timestamp at the top.

Related reading

We follow these rules

  • GDPR (EU 2016/679).
  • ISO/IEC 27001:2022.
  • NIS2 (EU 2022/2555).
  • HIPAA safe harbor under 45 CFR § 164.514(b)(2).

Our promise

We do not sell your data.

We do not train models on your text.

We store your files in Germany.

You can delete your account at any time.

You own your work.

Where we run

Our servers live in Falkenstein, Germany.

We use Hetzner. They hold ISO 27001 certification.

All data stays in the EU.

Backups run every day.

Need help?

Email support@anonym.legal.

We reply within one business day.

How we test

We run a full check suite on every release.

Each surface gets its own sweep script and report.

Human reviewers spot-check the output each week.

We track recall and precision on a labelled set.

Bad runs block the deploy.

What we never do

  • We never sell your information to third parties.
  • We never train models on what you upload.
  • We never keep your work after you delete it.
  • We never share keys with any outside firm.
  • We never run ads inside the product.

Plans in plain words

We sell credits, not seats.

One credit covers one short job.

Long jobs use a few credits each.

You can top up at any time.

Unused credits roll over each month.

Read the plans page for current rates.

Who built this

A small team of engineers and lawyers built this.

We ship from Europe and work in the open.

Our founder note spells out why we started.

Where to start

How the parts fit

A browser add-on cleans text inside Chrome.

A Word plug-in handles drafts in Office.

A small desktop tool works on whole folders.

An agent protocol link feeds large models safely.

All four share one core engine and one rule set.

Words from our team

We started this work after a lunch about cookies.

One friend kept getting odd ads on her phone.

We asked why a court file leaked through a draft.

We sketched the first build on a napkin that week.

By month three we had a tiny demo for a friend.

She used it on her first case the next day.

Common questions we hear

Can the tool read scanned PDFs? Yes, with OCR.

Does it work on long files? Yes, in small chunks.

Can I roll my own rule set? Yes, save it as a preset.

Does it run offline? The desktop build runs offline.

Do you keep my files? No, the cloud build wipes after each run.

Will it learn from my work? No, we never train on inputs.

A short tour of the workflow

Upload a file or paste a snippet of prose.

Pick the entities you want gone from the draft.

Choose a method: replace, mask, hash, encrypt, or redact.

Press run and watch the side panel show each hit.

Skim the result and tweak any rule that misfired.

Save the cleaned file or send it to a teammate.