Did you just run into a download or a file on your computer that has been digitally signed by Luth Research LLC? If so, please read on.
You'll typically notice Luth Research LLC when clicking to run the file. The publisher name shows up as the "Verified publisher" in the UAC dialog as the screenshot shows:

You can view the additional details from the Luth Research LLC digital signature with the following procedure:
Here's a screenshot of a file digitally signed by Luth Research LLC:

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 Luth Research LLC and that the file has not been tampered with.
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 see the address for Luth Research LLC, such as the street name, city and country.
VeriSign Class 3 Code Signing 2010 CA has issued the Luth Research LLC 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 Luth Research LLC files I've collected, thanks to the FreeFixer users.
| Detection Ratio | File Name |
|---|---|
| 0/48 | LuthIEPlugin.dll |
| 0/57 | LuthIEPlugin.dll |
| 0/55 | LuthIEPlugin.dll |
The detection percentage is based on the fact that I have gathered 160 scan reports for the Luth Research LLC files. 0 of these scan reports came up with some sort of detection. If you like, you can view the full details of the scan results by examining the files listed above.
The analysis is done on certificates with the following serial numbers: