Anonymize contracts for AI as in-house counsel
How to anonymize contracts for AI is a question for legal departments, in-house counsel and litigation teams who want to summarize a contract, compare two amendments or prepare a memo without exposing the parties. A distribution agreement, a dispute file or a trademark portfolio cites companies, executives, amounts and registration numbers that fall under trade secrets and the confidentiality of legal advice. Biffer processes these files on your computer, with no connection, and replaces each identifier with a stable alias.
This page describes the files concerned, the rules that protect them, the AI uses and the fields of the in-house counsel profile.
Contracts, litigation, intellectual property: in-house counsel's files
In-house counsel work on long, structured and almost always confidential files.
- Contracts and amendments (Word, PDF): parties, signatories, agreement or amendment number, price and exclusivity clauses.
- Dispute files: writs, written submissions, internal dispute number, French docket number (numéro RG), judgments with their decision number.
- Intellectual property: registration certificates, French trademark number (INPI, the French IP office), patent number, cease-and-desist letters for infringement.
- Legal opinions and memos: internal opinions, risk analyses, exchanges with outside counsel.
Biffer processes these PDF, Word, Excel, CSV and text files while preserving the formatting: clause numbering and appendix tables stay in place. A contract scanned as an image goes through built-in optical character recognition, offline, then is redacted by blacking out the pixels, with no possible restoration. For a contract received as a PDF, see the page redact a PDF.
Trade secrets and confidentiality: what protects these files
Three regimes overlap on in-house counsel's files. Trade secrets, defined in France by Law No. 2018-670 of 30 July 2018 in Articles L151-1 et seq. of the Commercial Code (transposing the EU Trade Secrets Directive), protect any information that is not generally known, has commercial value and is subject to reasonable protection measures: a distribution agreement or a litigation strategy qualifies. The confidentiality of in-house counsel's legal opinions, created by the French law of 20 November 2023, requires these opinions to be identified and kept as such. Finally, professional secrecy, punished under Article 226-13 of the French Criminal Code, binds the lawyers on the case.
The GDPR adds its own requirements for the individuals named: under Article 32, the controller must ensure the security of this data, including with regard to its service providers. Two consequences.
- Redacting a contract before submitting it to an online AI service is one of the reasonable protection measures that trade secret status requires: the content goes, the parties stay with you.
- A docket, trademark or agreement number makes it possible to find the case: it is redacted just like a name. With offline software, the original file stays at the source, in the legal department.
Biffer prepares, you validate: in-house counsel review the preview and have the final word on what is shared.
AI use cases and the Biffer workflow
Once pseudonymized, a contract or a dispute file is excellent material for an AI, because legal analysis is about clauses rather than the names of the parties.
- Summarize a hundred-page contract clause by clause.
- Compare two versions of an agreement to list the differences.
- Extract the obligations, deadlines and penalties of a framework agreement into a table.
- Draft an outline for a risk memo or a formal notice.
The workflow is always the same.
- You drop the file into Biffer with the in-house counsel profile enabled.
- The local analysis highlights companies, people, addresses, SIREN, dispute, docket, trademark, patent, minutes and agreement numbers.
- You untick false positives (a reference to a statute, the name of a court) and add what is missing, all occurrences at once.
- The document comes out with stable aliases (PERSONNE_001, LITIGE_001 for a dispute, MARQUE_002 for a trademark; the alias labels are in French); in Word and PDF, redacted data is highlighted in black, an option enabled by default.
- The mapping table, encrypted (Argon2id and AES-256-GCM) or in plain text, restores the values in the AI's answer.
The queue processes a whole file with the same aliases from one document to the next. Biffer is free for five files per month, after a one-time email confirmation in the software; beyond that, Biffer for Mac or Biffer for PC costs €10 excl. VAT (€12 incl. VAT) per computer, paid once: unlimited files, lifetime license, all redaction features included. The steps are detailed on the features page.
The fields the in-house counsel profile recognizes
The in-house counsel profile adds litigation, contract and intellectual property identifiers to the general detections. Here is the exact list, as it appears in the software.
| Field | Where you find it |
|---|---|
| Dispute number | Internal litigation tracking, provisions, exchanges with lawyers |
| Trademark number (INPI) | Registration certificates, oppositions, formal notices |
| Patent number | Industrial property titles, licenses, assignment agreements |
| Numéro RG (docket number) | Writs, written submissions, judgments |
| Minutes / decision number | General meeting minutes, court decisions, regulator decisions |
| Agreement / amendment number | Framework agreements, amendments, contract registers |
On top of these come the four fields shared by all professions (file number, reference, contract number, employee ID) and the general detections: people, emails, phone numbers, postal addresses, French company numbers (SIREN and SIRET), French social security number, IBAN, license plates, dates. For an identifier specific to your legal department, the custom keyword field described on the professions page does the rest. The lawyer profile can be added if needed. Biffer is published by Romain Rissoan, trainer, consultant and founder of OPCADIA, in Lyon.
Frequently asked questions
Are company names detected like the names of people?
Biffer's general detections cover individuals (last name, first name, title followed by a name), SIREN and SIRET numbers with key check, addresses, emails and phone numbers. A company name on its own, with no SIREN next to it, can look like an ordinary word: the preview then puts you in control and lets you add a missing value once, for all its occurrences. You select the company name, and every mention gets the same alias throughout the document, then in the other files in the queue. For a recurring counterparty, a custom keyword field saves you from repeating the operation.
Can clause numbers and statutory references be kept?
Yes, and that is the default behavior. Biffer targets precisely the data types it recognizes: people, contact details, professional identifiers and custom fields. A clause number ("Article 12.3"), a reference to a statutory article or the date of a regulation fall outside this scope and stay in place. Dates, however, are detected, because a signature or hearing date can identify a case; if your analysis needs them, the "keep" policy applies to the "date" type without touching the rest. The pseudonymized contract thus stays readable and usable by the AI for a clause-by-clause analysis.
How do you restore the real parties in the summary produced by the AI?
At export, Biffer offers to save a mapping table that links each alias to its original value. You encrypt it (Argon2id and AES-256-GCM) with a password, or leave it in plain text if it stays in an already protected location. When the AI returns a summary that mentions SOCIETE_001 or LITIGE_002, you load that text back into Biffer with the table: the real parties and references are restored, still on your computer. Without a table, the pseudonymization is irreversible. Either way, everything stays on your computer.
Your business documents anonymized, ready to be published or handed to an AI tool.
Biffer runs on your computer without sending a single file. Free for five files a month, unlimited for €10 excl. VAT per computer.
100% offline · Free: 5 files a month · No file sent