When is company unwelcome?

In a recent paper in this journal, Joshua Blanchard has identified a novel problem: the problem of unwelcome epistemic company. We find ourselves in unwelcome epistemic company when we hold a belief that is also held mainly or most prominently by those we regard as morally or epistemically bad. Blanchard argues that some, but not all, unwelcome epistemic company provides higher-order evidence against our belief. But he doesn't provide a test for when company is unwelcome or a diagnosis of why it is unwelcome. I provide both. On my disjunctive test, unwelcome epistemic company provides us with a defeater when either there is a match between the content of the belief and the properties that make our company unwelcome, or there is reason to suspect that the belief arose via a shared, unreliable, causal process.