These PDF files are digitally watermarked to signify that you are the owner. A small message is added to the bottom of each page of the PDF containing your name and the order number of your purchase.
Warning: If any files bearing your information are found being distributed illegally, then your account will be suspended and legal action may be taken against you.
Here is a sample of a page from a watermarked title:
This product is priced at $5.99
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