What does striking out text mean (and why Biffer is named after it)
Striking out text originally means drawing a line through written words to cancel them; applied to a document you are about to share, it means making its sensitive information unreadable, or replacing it with a neutral label. In French, the verb is "biffer" and the operation is "biffage", which dictionaries define as crossing out with a stroke of the pen. That is where our software gets its name: Biffer is French for "to strike out". Some French teams even say "biffing", an anglicized form of the same word, while English speakers usually call the operation redaction. All these words describe a single practice: removing from a file what must not leave it.
Striking out applies to very ordinary documents. An HR department sends an employment contract to its lawyer with the social security number and pay struck out. An accounting firm shares a balance sheet with a lender, hiding the names of the clients listed in the notes. A doctor sends an excerpt from a patient file to a colleague for an opinion, without the patient's identity. A tenant provides a tax notice with the tax number hidden.
In each case, the aim is to protect people while keeping the document useful. The GDPR treats as personal data any information relating to an identified or identifiable person (article 4 of the GDPR): a name, of course, but also a case number, an address or a date of birth. Striking out data in a document is the practical answer to this broad definition. It is close to redaction, pseudonymization and anonymization, with nuances worth knowing to choose the right technique.
Striking out, biffage, redaction: definitions and nuances
In French, "biffer" belongs to the vocabulary of administrative and legal writing. In a notarial deed, struck-out words are counted and approved at the end of the deed, so that no one can dispute what was crossed out. English has the same reflex in legal drafting, where deletions in a signed document are initialed by the parties. Adobe Acrobat Pro, in its French version, even uses the verb "Biffer" for the tool that permanently deletes sensitive content from a PDF, called Redact in English. Several related terms circulate in organizations:
| Term | What it means | Reversible? |
|---|---|---|
| Strike out (French: biffer, biffage) | Cross out, black out or replace information in a document | Depends on the technique |
| Redact | Remove or black out a passage before release | No, if the text is deleted |
| Strikethrough | Formatting that draws a line through text, which stays readable | Yes, the text is intact |
| Pseudonymize | Replace with an alias, with a table kept separately | Yes, with the table |
| Anonymize | Prevent any re-identification by reasonable means | No |
Note the trap in the third row: strikethrough formatting in a word processor leaves the text perfectly legible, so it protects nothing. Pseudonymization is defined in article 4 of the GDPR: the data can no longer be attributed to a person without additional information, kept separately. Striking out is the broadest word in this family. It describes the gesture, whatever the result sought: blacking out a passage, replacing it with a label or substituting an alias. The page redact a document covers the black-out variant, and the article what is redaction the history of that word.
Why strike out information before sharing a document
The first reason is regulatory. The GDPR sets a data minimisation principle: process only data that are "adequate, relevant and limited" to what is necessary (article 5). Sending a full contract when the recipient only needs its clauses means disclosing unnecessary data. For health data, article 9 of the GDPR adds a prohibition in principle, with strictly defined exceptions.
The second reason is professional secrecy. Lawyers, doctors, accountants, notaries and social workers are bound by it, and breaching it is a criminal offense in many countries: in France, article 226-13 of the Criminal Code punishes it with one year's imprisonment and a €15,000 fine. Striking out data lets you share a case, a document or a template without revealing the identity of the people concerned.
The third reason is practical. Striking out information is needed in everyday situations:
- asking a colleague or an expert for an opinion on a real case;
- producing a document for a court or an auditor, without third-party data;
- publishing an example, a template or a training case study;
- submitting a text to an AI assistant for a summary or a rewrite;
- answering an access request while removing data about other people.
Recital 26 of the GDPR also states that truly anonymous information falls outside the regulation. Careful striking out therefore reduces the scope of the data to protect, which simplifies what comes next. The fines provided for in article 83 of the GDPR, up to €20 million or 4% of worldwide annual turnover, show what is at stake.
Striking out text in practice: method and tools
Successful striking out leaves no usable trace. The most common trap is drawing a black rectangle over the text in Word or in a PDF: the text is still underneath, and a simple copy and paste brings it back. Metadata (author, company), comments, tracked changes and the file name can also contain personal data. The method takes five steps:
- Spot direct identifiers (name, email, phone, social security number, IBAN) and indirect ones (address, date of birth, unique role, case number).
- Choose the mode: black out, mask with a label such as [PERSONNE], or replace with a stable alias such as PERSONNE_001.
- Really delete the original text, rather than covering it.
- Clean the metadata, comments and revision history.
- Review the result from the recipient's point of view.
Tools range from manual work to specialized software. We designed Biffer, and gave it this French name, to automate these five steps on your computer, with no connection: the software detects names, contact details, French company numbers (SIREN and SIRET), IBANs, license plates and the fields of 18 professions, shows you a highlighted preview, then rewrites the Word, Excel, CSV, text or PDF file. Scans go through local character recognition before being blacked out. An optional encrypted mapping table lets you "unredact" the document later, once a third party or an AI returns it. Your settings are saved as reusable configurations, handy for processing the same type of document every month. Each step is detailed on the page features.
Strike out the data in your next document without it leaving your computer
Biffer, published by Opcadia and designed by Romain Rissoan, runs on Mac and PC, entirely offline. The free plan covers 5 files per month with every feature; unlimited use costs €10 excl. VAT (€12 incl. VAT) per computer, paid once.
Frequently asked questions
Is strikethrough formatting enough to hide text?
No. Strikethrough in Word or another editor draws a line through the words but leaves them perfectly readable, and the text stays in the file. To strike out information in the protective sense, the characters must be deleted or replaced, by a black bar, a label such as [PERSONNE] or an alias, then the metadata cleared.
Is a document with struck-out data anonymous under the GDPR?
Not always. If an alias replaces each name and a mapping table makes it possible to go back, the document is pseudonymized and remains subject to the GDPR. Without a table, when nothing allows the information to be cross-referenced any more, it comes close to anonymization.
Can I strike out text in a scanned PDF?
Yes, provided character recognition is used to locate the text in the image, and the corresponding pixels are then blacked out. Biffer performs both operations on your computer. Blacking out an image is permanent.
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