Hello Youssef,
As Shaun and Brian mentioned, BLT is a toolbox allowing you to distribute commercial LabVIEW applications with just a few easy steps. However it is limited to LabVIEW executable running on Windows. So this will not cover your need for licensing LabVIEW source code.
If you are looking to sell LabVIEW applications running as executable on Windows computers with advanced licensing scenarios, you should definitely look into BLT for LabVIEW.
You can try BLT for free with no time limitation, with all the features, and distribute 1 application on up to 5 computers. After that, there are some fees associated.
BLT does not only provide licensing features, but also auto-update capabilities, usage tracking and remote debugging tools.
You can get a lot of information regarding BLT for LabVIEW at https://BLTforLabVIEW.com and also by looking at the product documentation at: http://help.studiobods.com/bltforlabview
If you have any further questions feel free to send an email to contact@studiobods.com
Best regards.