The sale services, bundling, and jointly advertising strategies under profit sharing contract in closed-loop competitive supply chain

In this research, a two-level dual-channel CLSC and the coordination model has been achieved through combination of revenue sharing contract with a cost-sharing contract. In addition, recycling the waste used products is nowadays vital for all SCs and also advertising, to improve public information and introduce the products, is a factor that is worth investing jointly in. At result in this research, SC in three scenarios (decentralised, centralised, and coordinated) has been studied considering the Stackelberg game and using the Lagrangian approach and KKT conditions to achieve optimal decisions. Sensitivity analysis shows that sale service and bundling improve the total profit of SC and increase the number of sales. Bundling and sale services strategies helped SC not to be destroyed and not to be ineffective in the market. Also, analysis shows that investing in the advertisement is always beneficial, and joint advertising makes efficient collaboration in a competitive situation.