From a financial perspective, a civil lawsuit is rather like a derivatives con- tract. Its value to a claimant comes from the performance of an underlying asset—litigation—with an uncertain, potentially lucrative outcome. No surprise, then, that some see the allure of funding legal expenses upfront in exchange for a share of the proceeds if the case is won or settled. Payouts are uncorrelated with other markets, so investors can use them to diversify. The complexity of the asset makes it hard to price, which offers room for shrewd cal- culation. Throw in reports of fat returns from third-party litigation-finance (tplf) firms and it is easy to see why the industry is growing strongly. A survey by Westfleet Advisors, a litigation-finance broker, finds that commercial cases in America attracted $2.3bn of investment in the year to June.