The Courts have empirically played a principal role in developing Intellectual Property Law.

The reality of modern IP law thus diverges from the conventional constitutional allocation of lawmaking authority: Congress passes statutes, the executive branch implements them, and the federal judiciary interprets them in adjudicating cases and controversies. By contrast, intellectual property reflects a mixed heritage in which courts, operating in what can most aptly be characterized as a common law mode, came to play a principal role in fleshing out and evolving terse early legislative enactments. Although Congress has partially codified several of these judicial doctrines, the courts continue to play a central, although contextually variable, role in the evolution of IP law. As newer aspects of patent and copyright law have taken on greater legislative specificity, the mix between common law and statutory interpretation has shifted. Nonetheless, it would be a mistake to presume that legislative directive has supplanted the judiciary’s “common law” role in many important areas of federal IP law. This chapter traces the development and evolution of federal IP law. The history can usefully be broken out into three principal, although somewhat overlapping, phases: (I) the formative period, during which the courts fleshed out the early formulations with relatively broad and deep strokes; (II) the codification period, in which Congress integrated jurisprudence into statutory text while leaving more limited room for judicial innovation; and (III) the modern period, in which interest group politics has generated some highly detailed provisions. The final section of this chapter sketches some of the ramifications of this history for statutory interpretation.