AnonymFilesAnonymize a PowerPoint presentation (.pptx) before giving it to an AI
A PowerPoint sent to an AI carries much more than its visible slides: speaker notes, hidden slides, comments, properties and chart data. To anonymize it, remove these hidden layers, then replace the names in the visible text with labels on your computer.
What a .pptx file hides
A committee presentation, a client debrief deck or a due diligence deck passes from hand to hand. Each reviewer leaves traces in it. Before giving it to ChatGPT, Claude or a third party, go over these layers:
| Item | What it can reveal | In AnonymFiles |
|---|---|---|
| Speaker notes | The real talking points: client names, figures, frank opinions | Read and redacted |
| Hidden slides | An earlier version, an appendix pulled from the slideshow | Read and redacted like the others |
| Comments | Internal exchanges, reviewers' names | Never carried over into the copy |
| Document properties | Author, company, last modified by | Never carried over into the copy |
| Charts | The embedded Excel workbook, with all its rows | Never copied, neither data nor labels |
| Images and screenshots | A dashboard, an email, a client logo | Never copied |
| Invisible or off-slide objects | A text box forgotten in the margin | Their text is read and redacted |
| Visible slide text | Names, companies, addresses, amounts | Automatic detection, side-by-side review |
PowerPoint's Document Inspector
On Windows, PowerPoint offers a tool to remove hidden data: File > Info > Check for Issues > Inspect Document. According to Microsoft, it looks for and can remove:
- comments and ink annotations;
- document properties and personal information;
- revision tracking data;
- invisible slide content (objects formatted as invisible);
- the content of objects placed off the slide;
- presentation notes;
- custom XML data.
What the inspector does not do
The inspector cleans the hidden layers, not the content. It leaves in place:
- The visible text: the client's name on the title slide, the companies in an org chart, the amounts in a table.
- Objects covered by others: Microsoft states that it does not detect them.
- Animated off-slide objects, which are neither detected nor removed.
- Images added to the notes, which cannot be removed.
- Hidden slides: Microsoft's page does not list them among the items inspected. Delete them by hand if the AI does not need them.
- Chart data: a chart can embed an entire workbook. The safest option is to replace it with an image or remove it.
For the visible text, each name still has to be replaced by hand, consistently from one slide to the next. That is where a pseudonymization tool saves the most time.
Typical cases in a firm
- Audit or due diligence debrief: names of the target, its executives, key employees, suppliers.
- Committee or board deck: unpublished figures, acquisition projects, project code names.
- Internal training built on a real case file: a poorly anonymized client case, screenshots of practice-management software.
- Pleading or case presentation: parties, timeline, excerpts from exhibits.
In all these cases, the AI needs the line of reasoning, not the identities: summarizing, rewording, preparing speaker notes, turning a deck into a written memo.
The method with AnonymFiles
AnonymFiles is a desktop app, coming soon for Apple silicon Macs and Windows, that processes an entire folder: the presentation, but also the Word files, PDFs, emails and spreadsheets that go with it.
- Drop in the folder. The .pptx and the related documents. The original is never modified. Old .ppt files (PowerPoint 97-2003) are read too: slide text and speaker notes.
- Text extraction. The app reads the text of each slide, hidden slides included, and the speaker notes. Comments, properties, images, charts and embedded objects are never copied.
- Detection. Names of people, organizations, addresses, emails, phone numbers, IBANs, private dates and identification numbers become stable labels, such as [PERSONNE_1] or [ORGANISATION_1], the same as in the other documents in the folder.
- Side-by-side review. One click masks what detection missed: a project name, an amount, a product. Nothing is exported without approval.
- Export. The copy is a text file (Markdown), split slide by slide, with the notes under each slide. No formatting or images: the AI works on the text.
- Re-injection. Paste the AI's answer into the app: the real names come back in place of the labels, on the computer.
On the network side, the app works with no account and no telemetry, with the license checked on the computer and no network call. On a Mac, the detection models are included; on Windows, they are downloaded once, at the first processing run, without any document text. Price: €290 excl. VAT per seat per year for one or two seats, €240 excl. VAT per seat from three seats, quote above twenty seats.
Frequently asked questions
What does a PowerPoint file hide?
Speaker notes, hidden slides, comments, document properties (author, company), invisible objects or objects placed off the slide, and charts, which often embed their Excel data. Images and screenshots can also show names.
How do I remove notes and comments from a PowerPoint?
On Windows, in PowerPoint: File, Info, Check for Issues, then Inspect Document. The inspector finds and removes, among other things, comments, properties, invisible content, off-slide objects and presentation notes. Microsoft recommends using it on a copy, because the removal cannot always be undone.
Is the Document Inspector enough to anonymize a presentation?
No. It removes hidden data, but does not touch the visible text of the slides: client names, company names, amounts. According to Microsoft, it also does not detect objects covered by others, nor animated off-slide objects, and it does not remove images added to the notes.
Does AnonymFiles read speaker notes?
Yes. AnonymFiles reads the text of each slide, hidden slides included, and the speaker notes. It makes a text copy (Markdown), redacted with the same labels as the rest of the folder. Images, charts and objects are never copied.
Does the copy of a PowerPoint keep the layout?
No. The copy of a presentation is a text file, slide by slide, with no formatting or images. It is the safest format for an AI, which works on the text: summarizing a committee deck, rewording a slide, preparing a memo.
What about the text in charts and diagrams?
Charts are not carried over into the copy: neither their labels nor their data. If a figure or a name from a chart matters for the task, copy it into a text box or the notes before processing, so it is redacted with the rest.