Your documents
- Processed on the PC only. Every tool — conversion, compression, OCR, signing, redaction — runs locally. The software has no cloud service to send documents to.
- The AI is local too. Summarise, Translate and Ask this PDF run a language model on the PC itself. The model is downloaded once, then works with no connection at all.
- Originals are never modified. Every tool writes a new file.
- No accounts, no sign-in for users.
What leaves the PC
One connection is required: the licence check, over HTTPS, to pdfstudio-licence.elixtechs.com (or pdfstudio-licence.nmteches.com in 1.2.0 and earlier) — at activation, at periodic renewal and at deactivation. It sends:
| Item | Why |
|---|---|
| Licence key | To identify the licence and its seats |
| Machine ID | A SHA-256 hash of Windows identifiers and the computer name, salted with the licence serial — to count seats. The identifiers can’t be recovered from it, and it differs for the same PC under another licence. |
| Computer name | Sent so a licence administrator can tell PCs apart, but our server is currently configured not to store it for online activations. |
| App and Windows version | Compatibility and support |
Never sent: document content, file names, the Windows user name or usage telemetry.
Since 1.2 the app checks pdfstudio.elixtechs.com (pdfstudio.nmteches.com in 1.2) once a day for a newer version (the version, processor type and engine build only), and after a failure asks the user once whether to send error reports; no report is sent without that agreement, and file names, paths, names and licence keys are removed from it. Both can be turned off for every user with the policy key HKLM\SOFTWARE\Policies\NMTeches\PDF Studio.
Optional downloads (add-ons and AI packs) happen only when a user asks for them, and send nothing about documents. The full list is in Network and firewall.
What we store
| Record | Contents | Retention |
|---|---|---|
| Licence | Organisation name, contact email, seats, dates and included tools | For the contract, and as accounting records require |
| Machine activation | Hashed machine ID, app and Windows version, first and last contact, last IP address | While the PC is activated. The IP address is cleared after 30 days without contact |
| Event log | Operation and result, IP address, user agent, hashed machine ID — to detect abuse | 180 days, then deleted automatically |
| Offline activation request | The request code’s contents, including the computer name | With the licence record |
| This website | A daily-salted hash to count downloads, and what you type into the request form | See the privacy policy |
- All traffic is encrypted over HTTPS, and the app refuses to talk to the licence server without it.
- Access to the licence administration console requires single sign-on and a second factor, and every action in it is audited.
- We don’t sell or share data, and don’t use it for marketing.
Data inside output PDFs
PDF Studio adds a short record of what was done to each file it produces (up to 20 operations): the tool, the time, the source file names, the app version and non-secret options. Passwords are never recorded.
Data on the PC
- Settings, saved signatures and the job history live in
%APPDATA%\PDF Studio\in the user’s profile, under normal Windows permissions. - Log files in
%APPDATA%\PDF Studio\logs\stay on the PC, rotate at 5 MB, and never contain licence keys, activation records or document content — though they can include file paths. - The job history keeps file paths only, and can be cleared from the History page with Clear.
- The PDF engine runs as a separate process that listens only on
127.0.0.1, and refuses any request without a secret token that changes on every launch. - The app needs no administrator rights while running, and installs no Windows services or background agents.
Keys and signatures
- Licence keys are signed with Ed25519. The app verifies the signature locally, so a key can’t be forged or have its seats changed.
- Activation records are signed by the licence server with a separate key, tied to one PC, and expire. Copying one to another PC doesn’t work.
- The private signing keys never leave our infrastructure and are excluded from backups.
- The app detects a clock set backwards and stops rather than accept an expired activation.
Download integrity
- Every published file has a SHA-256 checksum on the download page. Verify it before distribution:
certutil -hashfile <file> SHA256. - We verify every file against its checksum when publishing, and again after it is stored.
- Files are served through short-lived signed links from private storage, not from a public folder.
Open-source components
PDF Studio is two programs under two licences:
- The desktop application — the interface, menus and licence activation. Proprietary, © ElixTechs (formerly NMTeches), licensed under the End User Licence Agreement.
- The document engine (
pdfsvc) — the program that processes PDFs, running as a separate process on the PC. Published as free software under the GNU AGPL version 3 or later, because it uses PyMuPDF and MuPDF.
The engine’s complete source code, its licence text and a list of every component and its licence (including pikepdf, RapidOCR and Arabic fonts under the SIL Open Font Licence) are installed with every copy, in
resources\source. We also provide the complete corresponding source of each release on request for at least three years.
Reporting a vulnerability
Found a security issue? Email us [email protected] with “Security” in the subject and steps to reproduce. We acknowledge within two working days, and ask that details stay private until a fix is released.
Didn’t find what you need?
Check the FAQ, or write to us and we will reply within one working day.