One of the most requested and hence actively developed features in GroupDocs.Viewer for .NET is watermarking. Watermarking allows you to protect documents that you display on the web from screen-grabbing. In GroupDocs.Viewer for .NET watermarks are implemented as customizable text that can be added over a displayed document, overlapping its content. For the first time the ability to add watermarks was implemented in GroupDocs.Viewer for .NET version 2.0. In its first implementation, the feature had a number of restrictions....let users download and print PDF versions of the original files...Let’s start with the method signature: public ClientHelper Watermark(...