For nearly every fraudulent investment scheme that raises over $1 million from the investing public, the perpetrators will likely need support from third‐party entities to be able to operate and grow the scheme. Those entities often become involved and assist the scheme in one way or another – and could potentially become liable to investors victimized by the scheme. The usual suspects include banks, underwriters, self‐ directed IRA custodians, clearing services, lawyers, accountants, other professionals. In certain instances – such as when they acquire sufficient knowledge of the scheme or breach an independent duty – those entities may be held liable to the investors. This presentation is a primer on secondary liability in connection with fraudulent investment schemes. It discusses the legal framework for cases against third parties, various types of third parties that may be held liable, and types of claims that may be asserted against them.