You can’t invest in American law firms—yet. But it’s only a matter of time. We live in an age where just about any income-generating asset one can imagine, from home loans to professional football players, has been securitized, collateralized and sold to investors. So you might expect there would be no ubiquitous class of large, highly profitable businesses that has failed to tap their receivables for capital. But if so, you’re wrong. Consider the American law firm and its peculiar partnership-based capital structure.