The Adobe Reader can validate the digital signature on digitally signed PDF files. It can do that automatically when a PDF document is opened in the viewer. However, it is a configuration setting that determines if it does that or if you should do it manually.
![](https://www.bullzip.com/kb/wp-content/uploads/2022/09/image.png)
The image above shows what it may look like if the signature isn’t validated. You can right-click it and select Validate Signature to make Adobe Reader perform the validation.
![](https://www.bullzip.com/kb/wp-content/uploads/2022/09/image-1.png)