One enduring historical debate concerns whether the American Constitution was intended to be -- referring to a theory of statecraft that maximizes the role of private markets and minimizes the role of government in economic affairs. The most central and powerful proposition of classical constitutionalism is that the government's role in economic development should be minimal. First, private rights in property and contract exist to any community needs for development. Second, if a particular project is worthwhile the market itself will make it occur. Third, when the government attempts to induce development politics inevitably distorts the decision making. The result is excessive state involvement, with benefits typically going to well placed interest groups.From the Colonial period until the mid-nineteenth century American legislatures and courts conceived of the patent as an active tool of economic growth. States in particular granted patents in anticipation that the grantee would actually develop some work of public improvement. This conception of the patent was distinctly pre-classical in the sense that it envisioned considerable state involvement in ensuring that granted patents were put to appropriate use. In addition, state issued patents, although not federal patents, were issued to promoters -- that is, to those who did not really claim to have invented anything new, but rather promised to develop technology or infrastructure in a new place.A few decades later a much more classical conception of the patent emerged, as a property right pure and simple. Questions about whether and how to employ a patent were lodged almost entirely with its owner, who at the high point of patent classicism even had the power to use patents to keep technology off the market -- precisely contrary to what the original framers of the provision had in mind.An essential part of this development was the rise of federal patent exclusivity -- a result that was not mandated by the text of the Constitution's IP Clause, particularly when read against the Tenth Amendment. The sources of increased hostility toward state issued patents were twofold. First was the view that state issued patents burdened interstate commerce. For example, the Supreme Court struck down the state-issued steamboat patent under the Commerce Clause, not under the Constitution's IP Clause. Second, however, only federal exclusivity could effectively limit the power of the states to grant unwarranted exclusive rights to favored grantees. The eventual result was a regime in which Congress acquired the exclusive power to award patents for inventions.Changes in United States patent law under the 1836 Patent Act and later were driven by classical beliefs that monopoly is bad and generally unnecessary for economic development, with invention as a narrow exception. This entailed, first, that the conditions for obtaining a patent be narrow, limited to actual inventions within the applicant's possession, and adequately disclosed. Second, patent issuance had to be made a nonpolitical, administrative action. The applicant was entitled to a patent if he could make specific showings concerning technology and use. The prior art queries that increasingly dominated patentability doctrine focused on what had been available in the past, rather than what economic development might require for the future. Finally, once a patent was issued the government very largely abandoned its interest. The patent entered commerce as personal property, creating individual rights but few social obligations. Together these requirements led both Congress and the courts away from relatively open ended policy concerns, and toward technical specification and boundary clarity. The result was a patent system increasingly detached from questions about economic development.