<p>Product reviews have strong influence on customers’ purchase decisions. However, authenticity of these reviews may be compromised due to inflation by online sellers in an e-commerce supply chain. In this paper, we analyze the extent of product review inflation under scenarios where product is offered by third-party seller or platform. Specifically, we consider a model setup where an online platform exerts effort towards detecting review inflation, and consider two mechanisms to combat review inflation: (i) <i>Incentive mechanism</i>, where social planner pays some incentive to the platform if it detects and reports fake reviews, and (ii) <i>Liability mechanism</i>, where platform and third-party seller share the liability cost paid to customers if review inflation is detected. We find that the third-party seller may set higher inflation level under liability mechanism depending on customers’ ability to detect inflation. Furthermore, social planner may need to be more vigilant towards third-party seller compared to platform.</p>