Work Package 7 (WP7) of the Progress on Meshed HVDC Offshore Transmission Networks’ (PROMOTioN) Horizon 2020 project focuses on various legal, financial and economic aspects of developing an integrated offshore infrastructure. Task 7.2 focuses on the development of an economic framework for the offshore grid in terms of three building blocks namely: planning, investment, and operation. The WP7.2 intermediate report consists of a compilation of five regulatory challenges that have been addressed and are related to two building blocks: Planning and Investment. The third building block (offshore grid operation) will be treated in the final report (April 2019). 1. Offshore grid planning comprises of three topics namely: CBA methods, onshore-offshore coordination, and public participation. 2. Offshore grid investment comprises of four topics. However, in this intermediate report, only the first two: cooperation mechanisms for renewable support, and transmission tariffs are treated. The remaining two topics 1) Investment incentives 2) CBCA methods would be addressed in-depth in the coming months of this project.