[6] The Federal Circuit had reached a contrary result in Interpart Corp. v. Italia,[7] upholding a California law prohibiting plug molding.

"[11] Thus, as such past decisions as Sears and Compco "have made clear that state regulation of intellectual property must yield to the extent that it clashes with the balance struck by Congress in our patent laws."

The prior Supreme Court decisions "correctly concluded that the States may not offer patent-like protection to intellectual creations which would otherwise remain unprotected as a matter of federal law.

"[12] The Federal Circuit, in its Interpart opinion argued that a plug-molding statute "prevents unscrupulous competitors" from taking advantage of the work of the originator while leaving later comers free to design and manufacture their own products, and "the patent laws say nothing about the right to copy or the right to use, they speak only in terms of the right to exclude.

"[13] First: "Appending the conclusionary label 'unscrupulous' to such competitive behavior merely endorses a policy judgment which the patent laws do not leave the States free to make."

That decision is left to the federal government and its determination was that copying the functional attributes of unpatented products that are in general circulation "is legitimate competitive activity.

"[15] This is a field that Congress has fully occupied, leaving no room for parallel state regulation, whether conflicting, complementary, or supplemental: [T]he federal standards for patentability, at a minimum, express the congressional determination that patent-like protection is unwarranted as to certain classes of intellectual property.

The Florida law substantially restricts the public's ability to exploit an unpatented design in general circulation, raising the specter of state-created monopolies in a host of useful shapes and processes for which patent protection has been denied or is otherwise unobtainable.

The patent statute's careful balance between public right and private monopoly to promote certain creative activity is a scheme of federal regulation so pervasive as to make reasonable the inference that Congress left no room for the States to supplement it.