podpis.sk uses a local bridge, so PDF and ASiC files are not uploaded to a remote server for signing or validation. The private signing key never leaves the identity-card chip.
If you do not want to install the bridge, you can explicitly select server validation. The document is then sent to podpis.sk and the local-processing guarantees do not apply to that validation.
The browser sends the document only to a local component at 127.0.0.1. The bridge prepares a new PDF revision, the eID chip creates the signature and the local component inserts it into the document. Neither the document nor its content is sent to podpis.sk.
The private key is created and protected inside the eID chip. Signing takes place on the card after KEP PIN confirmation; the application receives only the resulting signature value, never the private key.
EU DSS runs inside the local bridge and analyses the document on your computer. Internet access is used only for trusted lists and certificate status through OCSP/CRL; the document is not sent to podpis.sk.
When requested, the TSA receives only the cryptographic digest required to issue a timestamp, not the PDF or its text.
A service that requires an upload creates another point of access to document contents and risks related to transmission, logs, temporary files, backups or server misconfiguration. The local podpis.sk architecture removes this exposure and provides stronger privacy.
Keep the bridge and operating system updated. Local processing cannot protect against malware already present on the computer or intentional sharing of the resulting file.
In browser developer tools, document requests are directed only to 127.0.0.1. The remote server supplies the website and update information, not your document content.