Briksoftware has announced PDFKey Pro 4.3 (http://pdfkey.com) for Mac OS X and Windows. It’s an upgrade of the utility that locks and unlocks password-protected PDF documents.

PDFKey Pro removes editing and printing passwords by creating exact copies of PDF documents, but without the password. It instantly removes viewing passwords, but only if said password is provided beforehand. You can lock PDF files by creating perfect copies, but protected with either, or both, a viewing password and a password to restrict usage permissions (printing and copying) to the files.

PDFKey Pro 4.3 offers improved support for files with digital signatures, better compatibility with partially corrupted files, enhanced Mac OS X and Windows integration, and simplified usage of the integrated command line tools. It also adds German, French, Dutch and Polish localization

PDFKey Pro isn’t designed to defeat DRM systems and will not decrypt eBooks or other DRM protected materials. It requires Mac OS X 10.7 or later.

PDFKey Pro 4.3 is available as a full-featured free demo that lets you process the first page of each PDF document. This limit is removed by purchasing an activation code, priced US$24.99. Existing users of PDFKey Pro 4.x can upgrade for free.