The following are instructions on how to create a custom dynamic stamp in Adobe Acrobat X.
Note: You must have your Adobe Acrobat
‘Identity’ filled out for the software to know what name to use. This can be
completed by pressing CTRL+K with Adobe Acrobat open, then selecting the
Identity field.


Once the image is selected and shown in the sample field, click OK

Name your new custom stamp and select the Dynamic category, then click OK.

At this point, you have a basic image that can be used as a Stamp in Acrobat. The following steps show how to make the image include the name of the user who placed the stamp, as well as the time and date the stamp was placed.
Open a file explorer window and navigate to the following file path: %appdata%\Adobe\Acrobat\10.0\Stamps


Once in Edit mode, Select: Add New Field > Text Field
Click on your stamp to place the new text field, and adjust its placement and size as required.
Next, right click on the new text field and select Properties.
With the Text Field Properties open, select the Calculate tab > Custom Calculation Script: and then the Edit button to the right of the Script field.

This will open a Javascript editor.
For an auto-filled name and date enter the following code EXACTLY, then click OK.
event.value = identity.name + " at " + util.printd("h:MM tt, mmm dd, yyyy",new Date());

Close out of the Properties box and verify that your new stamp looks as expected and that it is sized and positioned appropriately
Note: the Title of the text field may overlap and obscure some of the generated text. This will not be shown when the stamp is used.

Congratulations! You now have a custom Stamp with dynamic content!