Thanks for
your request. What you need is Aspose.Words. Using Aspose.Words you can add
watermarks to MS Word document and convert them to PDF. Please follow the links
to learn how to insert watermarks and convert documents to PDF:
If you want to add watermark in an existing PDF file, you may use Aspose.PDF for .NET. Please see the following topics to get an idea of different types of watermarks which can be added, in an existing PDF file, using Aspose.PDF: