Telerik Reporting is licensed on a per-developer basis, so any developer who uses the report designers to design reports, and/or any developer who creates the reporting application and integrates the platform specific Report Viewers needs to have a developer license in their name. Licenses are not tied to specific machines, so a developer holding a valid license can install Telerik Reporting on more than one development machine, and deployed applications that integrate Telerik Reporting do not need a license set up on the Build, Staging or Production Servers. Developers are free to use their license to build reporting functionality into an unlimited number of applications.
End users who interact with the reporting features of your desktop or web-based application do not need any licensing. There are not any run-time fees associated with Telerik Reporting. It is simply licensed "per developer" as covered above.