One of the simple and best solution to apply watermark to multiple PDFs is to use PDF Watermark Creator A few days back one of my friend was also facing the same issue and I suggested him to use this professional solution to insert watermark in PDF files.
Must say this tool easily add image or text watermark on multiple PDF documents. Visit at more info; http://www.pdfwatermark.filefixutility.com/

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PDF watermarking software used for watermarking of PDF Documents, PDF Watermark software also known as PDF Stamp of PDF Copyright application. PDF watermarking can do with text as well as images. You can also crop the image before using it for
watermarking. PDF watermarking software can change the image size, shape, angle and also set the resolution of the Images. This software can manage the PDF documents by inserting the copyright image in user-defined location, position, and angle. PDF
watermarking also help to insert the links with PDF pages. Visit here: https://www.osttopstapp.com/pdf-watermark.html

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