Spectrum scarcity is one of the most important problems in modern mobile networks. In order to satisfy continuously increasing traffic demands, new approaches are needed to improve the efficiency of spectrum utilization in mobile networks. One of the promising solutions is spectrum sharing that allows multiple operators to use the same spectrum bands in an opportunistic manner. In this paper, we propose a new game theoretical framework for multioperator spectrum sharing in 5G heterogeneous networks. The novelty of this approach is that it takes into account both licensed and unlicensed spectrum bands. This feature allows multiple network operators to utilize unlicensed spectrum opportunistically while keeping the fair coexistence with WiFi networks. Simulations results show that using the proposed framework all competing operators achieve better performance, comparing to conventional spectrum sharing solutions.