Most Intel FPGA (formerly Altera® FPGA) software requires you to use a license to enable the software. The license is provided in a file named license.dat. The free Quartus Prime Lite Edition, legacy Quartus II Web Edition (v8.1 and later), and ModelSim-Altera Starter Edition software do not require a license.
A software subscription enables the Quartus Prime (and legacy Quartus II) software (including the IP Library) and the ModelSim‑Intel FPGA Edition software. When you purchase a software subscription, the license file supports the version of the software you purchase, all previous versions, and all versions released within a year of the purchase date. You can use the version of the software you purchase, and all related software, including the ModelSim‑Intel FPGA Edition software and the IP Library, indefinitely.
We also use licenses to enable additional software, such as purchased MegaCore functions, the Intel FPGA SDK for OpenCL, and the Intel SoC FPGA Embedded Design Suite (EDS).
For detailed information on licensing our software, refer to: