Consignment stock policy in a closed-loop supply chain

The main feature of sustainable supply Chain Management is reuse of end of life (EOL) products to reduce the environmental pollution. This paper considers the consignment stock (CS) policy for a closed-loop supply chain (CLSC). To achieve the economic goal, this study presents a multi-echelon supply chain with a single manufacturer, a single retailer and a third-party service provider. The objective is to optimize this three-level CLSC under a Stackelberg game scenario. The other objective is to identify the environmental impact of remanufacturing EOL products. In this CLSC, the manufacturer acts as the Stackelberg leader and the retailer, the third party are the followers. Under manufacturer’s leadership, the retailer and the third party acquire three different decision strategies – I, II, and III. In decision strategy I, the retailer acts as the leader and the third party acts as a follower, whereas in decision strategy II, they obtain a Nash game strategy. In the decision strategy III, they act as one unit and decide their decisions centrally. Numerical example and sensitivity analysis are used to illustrate optimal results of different decision strategies and also check the behaviour of key model-parameters. The best outcomes are found in decision strategy I. The main findings of our study show that when upper level player has more power then the supply chain gives best outcomes