How to lock a pdf from editing without adobe acrobat?

PDFsam Basic is an open-source desktop tool that can be used to lock PDF files against editing without using Adobe, but it only provides basic PDF permission protection, and its advanced security features are somewhat limited. This offline, open-source desktop program is a convenient local solution for locking PDF files against editing without using Adobe.

It allows you to encrypt PDF files with separate user and owner passwords to prevent editing, and supports offline batch processing of multiple files.

First, download and install the software from the official website, then launch it on your computer.

Select the Protection module from the left sidebar and add all target PDF files to the task list.

Set the viewer password and owner password to restrict editing as needed.

Click the Run button to generate a fully locked, encrypted PDF document.

Once processing is complete, the generated PDF file will prevent all editing, copying, and printing operations without the owner password.

Its advantages include: completely offline file processing, with no need to upload data to the cloud; open-source code; and the ability to encrypt multiple PDF files in batches simultaneously.

Its disadvantages include: it offers only basic security controls and lacks advanced permission settings; its text-based interface lacks intuitive visual controls; and it has no built-in feature to recover forgotten PDF passwords.

All files are processed locally, without the need to upload them to the cloud, thereby ensuring the security of confidential documents. If you wish to avoid using Adobe Acrobat, you can use this open-source tool; however, its basic security features should be carefully evaluated when it comes to strict protection of business documents.