Requirements for PDF Redaction
Legal and administrative requirements are increasingly placing more documents in the public domain, and electronic documents, including PDFs, are no exception. Before publishing these files, however, it is necessary to redact a PDF either manually or through batch software. There are several techniques as to how to redact a PDF properly, and avoid common mistakes that might lead to inadvertently leaving data in the redacted PDF file. An example is to make the text the same color as the background or to put a rectangle around the text, which allows one to highlight the text easily and read it.
Using Acrobat's Built-in Tool
The full version of Adobe Acrobat comes with a tool for automatic redaction, and offers several options. When you start to redact a PDF using this tool, it parses the document automatically, identifies private data according to criteria you set, removes the data, and then creates a new file so that one cannot access redacted data anymore. It can also load a pre-defined wordlist and search the document according to this list. It is relatively easy and fast to redact a PDF using this tool. Acrobat has also released a short video on their website which takes you through the steps and teaches you how to redact a PDF.
Batch Mode Redaction
You can also use stand-alone plug-ins that can handle a large number of files, and let you redact a PDF in batch mode, thus saving you considerable amount of time. Batch mode redaction of a PDF, however, should be used with caution, and always check some files randomly to make sure that no clues as to the missing data is left behind inadvertently. Once you have had some practice, and mastered the art of setting up proper filters, go ahead and redact a PDF with confidence.