For maximum privacy and control, you need to self-host any available open-source PDF editors on your own server.

If you want to sign a PDF, this post talks of free tools that let you add a signature to PDF. Type or draw a signature using them.

If PDF text or content disappears when editing, saving or printing files using Adobe, Foxit, etc, then this post will help you troubleshoot the issue.

When notarization occurs, a notary public certifies the authenticity of any signature appended to a document.

A prospectus is a document publically traded companies use to inform the public about an offering of securities, including the risks and financial outlook.