The U.S. Supreme Court’s relationship to patent law sometimes seems like that of a non-custodial parent who spends an occasional weekend with the kids. The custodial parent is, of course, the U.S. Court of Appeals for the Federal Circuit. . . . The Supreme Court controls the frequency of its patent law visits, and it is free to grant certiorari more often if it is unhappy with the Federal Circuit’s stewardship. . . . When each of these Supreme Court visits eventually comes to an end and everyday life resumes, it becomes plain once again that the Federal Circuit is, for all practical purposes, the parent in charge.

Though KSR International Co. v. Teleflex, Inc. is now widely acknowledged in the bar and the academy to be the most significant patent case in at least a quarter century, that view dramatically underestimates the importance of the decision. The KSR decision has immense significance not merely because it rejected the standard of patentability that had been applied in the lower courts for decades, but also because it highlights many separate trends that are reshaping the patent system.

The recent Supreme Court review of KSR v. Teleflex, eBay v. MercExchange, and Microsoft v. AT&T manifests the Court’s current interest in the patent jurisprudence of the Federal Circuit. Now it is evident that the Court has a level of concern sufficient to guarantee the possibility of grant of certiorari—whereas formerly a case could rarely generate sufficient interest for review. For long-range importance in patent law, KSR stands alone as the single most important Supreme Court patent decision on the bread and butter standard of “obviousness” in the more than forty years since the 1966 Graham v. John Deere. KSR will remain the leading interpretation of the Graham standard for quite some time.

The U.S. House of Representatives began September by passing the Patent Reform Act of 2007. This bill, if enacted, would make major changes to U.S. patent law. Given the universally recognized need for improvements to the U.S. patent system, passing a patent reform bill in the House should have been easy. It was not. . . . What made for such tough congressional sledding?

The Supreme Court in KSR v. Teleflex clarified its 1966 decision in Graham v. John Deere, avoiding the sea change to a synergy-based standard that many had expected—and perhaps feared. KSR has raised the bar set in Graham for seeking patent protection—by providing a flexible test for obviousness—while simultaneously making it easier for accused infringers to defend themselves. Moreover, KSR will change the strategies of both patent prosecutors and litigators.