If you want to protect your PDF from being used improperly, you'd better add unique watermark to your PDFs. PDFelement can help you to achieve it by adding text or image watermark to any page you like.
Code:
[B][FONT=Times New Roman][COLOR=windowtext][COLOR=windowtext][FONT=Times New Roman][B]youtube.com/watch?v=zSAKneyzHSU[/B][/FONT][/COLOR][/COLOR][/FONT][/B][FONT=Times New Roman][COLOR=windowtext]
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