Intel® MPI Library User's Guide for Linux* OS
There are two different licensing options:
Intel® MPI Library Runtime Environment (RTO) license. The license covers everything you need to run Intel® MPI Library-based applications and is free and permanent.
Intel® MPI Library Software Development Kit (SDK) license. This license covers all of Runtime Environment components as well as the compilation tools: compiler drivers (mpiicc, mpicc, and so on), files and modules, static (.a) libraries, debug libraries, trace libraries, and test sources. This license is fee-based, with several options described in the product end-user license agreement (EULA).
For licensing details refer to the EULA, or visit http://www.intel.com/go/mpi.