The increasing prevalence of store brands has attracted both retailers and national manufacturers to participate in store brand operations. However, retailers face a strategic decision regarding whether to disclose the national manufacturer's identity information, especially considering the impacts of the brand spillover effect and online reviews. This research investigates the retailer's disclosure strategy by developing a two-period model and exploring how this decision impacts online review ratings. Our findings illustrate that although the brand spillover effect of disclosing the national manufacturer's identity information can elevate consumers’ quality expectations for store brands, the influence of online reviews may diminish or even reverse this benefit. Specifically, a stronger brand spillover effect may adversely affect both parties and thus inhibit the retailer from disclosing such information, which is different from the conventional wisdom. Moreover, we demonstrate that disclosing the national manufacturer's identity is not advantageous for the retailer when the degree of the brand spillover effect is relatively low, consumers are more reference-dependent and rely more on online reviews to formulate quality expectations, and the quality level of the store brand is perceived as moderate. Finally, we consider several extensions, including strategic consumers, distinct pricing power structures, the effect of the national brand's online reviews, asymmetric consumer numbers, and heterogeneous consumer ratings, which either confirm the robustness of our findings or enrich the basic findings.

In reaction to evolving consumer preferences, prominent platforms, such as Amazon and JD, have progressively established proprietary store brands. However, the problems related to the sourcing of store brands and the disclosure of their quality information remain uncertain. To fill this gap, this paper utilizes game theory to develop a supply chain consisting of a national brand manufacturer, a third-party manufacturer, and a platform, focusing on the platform’s optimal sourcing strategy—determining whether to source its store brand from the national or third-party manufacturer—while also considering its quality disclosure strategy. We then examine how essential elements, specifically the brand spillover effect and the disclosure cost, influence these strategic decisions. Our research reveals that the quality information disclosure of the store brand occurs when the product quality surpasses a predetermined threshold. Additionally, although the elevated disclosure cost consistently diminishes quality disclosure, the impact of the brand spillover effect on quality disclosure is nonlinear. Finally, the platform’s sourcing strategy depends greatly on the brand spillover effect and the disclosure cost. Specifically, when the brand spillover effect is relatively large (small), the platform prefers to source the store brand from the national (third-party) manufacturer; with a moderate brand spillover effect, a higher (lower) disclosure cost encourages the platform to source from the national (third-party) manufacturer.