Did you just find a file that has a digital signature from PKWARE, Inc.? If that's the case, please read on.
You'll typically notice PKWARE, Inc. when clicking to run the file. The publisher name is displayed as the "Verified publisher" in the UAC dialog as the screengrab shows:

You can view the additional details from the PKWARE, Inc. digital signature with the following steps:
Here's a screencap of a file that has been digitally signed by PKWARE, Inc.:

As you can see in the screenshot above, Windows reports that "This digital signature is OK". This implies that the file has been published by PKWARE, Inc. and that no one has tampered with the file.
If you click the View Certificate button shown in the screenshot above, you can see all the details of the certificate, such as when it was issued, who issued the certificate, how long it is valid, and so on. You can also examine the address for PKWARE, Inc., such as the street name, city and country.
VeriSign Class 3 Code Signing 2004 CA and VeriSign Class 3 Code Signing 2010 CA has issued the PKWARE, Inc. certificates. You can also examine the details of the issuer by clicking the View Certificate button shown in the screenshot above.
The following are the PKWARE, Inc. files I've gathered, thanks to the FreeFixer users.
| Detection Ratio | File Name |
|---|---|
| 0/43 | PKArchive85u.dll |
| 0/57 | pkarchive89u.dll |
| 0/68 | PKTray.exe |
The detection percentage is based on the fact that I have gathered 168 scan reports for the PKWARE, Inc. files. 0 of these scan results came up with some sort of detection. You can view the full details of the scan results by examining the files listed above.
The analysis is based on certificates with the following serial numbers: