Reaffirming the Standard for Obviousness in Patent Law: Conor Medsystems Inc v. Angiotech Pharmaceuticals Inc & Ors ([2008] RPC 28)

Introduction

The case of Conor Medsystems Inc v. Angiotech Pharmaceuticals Inc & Ors ([2008] RPC 28) represents a pivotal moment in United Kingdom patent law, particularly concerning the doctrine of obviousness and the inventive step required for patent validity. The dispute arose over a European patent held by Angiotech Pharmaceuticals Inc (Angiotech) and the University of British Columbia, which claimed a stent coated with Taxol for "treating or preventing recurrent stenosis."

The primary parties involved were Angiotech Pharmaceuticals Inc, the patentees, and Conor Medsystems Inc, an American competitor challenging the patent's validity on the grounds of obviousness. The case traversed multiple jurisdictions, with prior decisions in the United Kingdom and the Netherlands influencing the eventual outcome at the House of Lords.

Summary of the Judgment

The central issue in the case was whether the patented invention—a Taxol-coated stent—was obvious to a person skilled in the art at the time of the patent application. Conor Medsystems successfully challenged the patent's validity in the UK, leading Angiotech to appeal to the House of Lords. The House of Lords ultimately upheld the patent, reinforcing the standards for assessing obviousness and the inventive step in patent law.

The judgment delved into the intricate balance between encouraging innovation through patent protection and preventing monopolies over solutions that are readily apparent to experts in the field. The House of Lords emphasized the necessity for a clear inventive step beyond merely trying an obvious solution, thereby setting a significant precedent for future patent disputes.

Analysis

Precedents Cited

The judgment extensively referenced several key precedents that shaped the court's approach to obviousness:

Johns-Manville Corporation's Patent [1967] RPC 479: This case introduced the notion that an invention could be deemed obvious if a person skilled in the art would consider it worthwhile to "obviously try" the proposed solution.
AGREVO, Case No T 0939/92: Pertained to the inventive step required when claiming broad classes of chemical compounds, emphasizing that technical effects must be uniformly applicable across the claimed group.
Halliburton Energy Services Inc v Smith International (North Sea) Ltd [2006] EWCA Civ 1715: Addressed procedural aspects in cases where one party does not oppose a patent, guiding the House in handling such situations.
Generics (UK) Ltd v H Lundbeck A/S [2007] RPC 32: Highlighted the multifaceted considerations in assessing obviousness, including the motive to find a solution, the number of research avenues, and the expectation of success.

These precedents collectively underscored the necessity for a substantial inventive step and cautioned against conflating obviousness with mere experimentation without sufficient expectation of success.

Legal Reasoning

The court's legal reasoning centered on refining the application of the obviousness standard in patent law. It distinguished between two interpretations of what constitutes an obvious invention:

Obvious to Try with Expectation of Success: If a skilled person would foresee a reasonable chance of success, then trying an obvious solution could lead to an obvious invention.
Obvious to Try without Expectation of Success: If the solution is to be tried without any substantial expectation of success, deducing an inventive step becomes problematic.

In this case, the House of Lords determined that the specification of the patent provided sufficient direction to consider Taxol as a viable agent for preventing restenosis. The Court criticized the lower court's conflation of obviousness with sufficiency of disclosure, emphasizing that the inventive step should be assessed based on the claimed invention's novelty and non-obviousness, independent of experimental sufficiency.

The judgment also addressed the pitfalls of the "obvious to try" doctrine, particularly in high-stakes, high-reward fields like pharmaceuticals, where vast resources are dedicated to exploring numerous potential solutions. The Court held that merely suggesting a direction for experimentation does not inherently possess an inventive step unless it demonstrates a clear advancement over existing knowledge.

Impact

The decision has profound implications for future patent applications and litigation:

Clarification of Obviousness: The judgment provides a more stringent framework for assessing obviousness, particularly discouraging challenges based solely on the idea that an inventor might have tried an obvious solution without a substantial expectation of success.
Strengthening Patent Validity: By upholding the patent, the Court reinforced the protection of innovations that, while seemingly straightforward, require a nuanced understanding and application of existing knowledge.
Guidance for Patent Drafting: Inventors and patent attorneys are now better informed about the necessity of demonstrating a clear inventive step beyond the mere suggestion of an idea, thus influencing how patents are drafted and argued.
Influence on Pharmaceutical Patents: Given the high stakes in pharmaceutical innovations, this ruling sets a precedent that may lead to more robust defenses of patents against obviousness challenges, ensuring that genuine innovations are adequately protected.

Complex Concepts Simplified

Obviousness in Patent Law

Obviousness refers to whether an invention is sufficiently inventive or if it is something that would be obvious to a person with ordinary skill in the field at the time the invention was made. If an invention is deemed obvious, it cannot be patented.

Inventive Step

The inventive step is a key criterion in patent law that assesses whether an invention is non-obvious and sufficiently innovative compared to existing knowledge.

Restenosis

Restenosis is the re-narrowing of an artery after it has been treated with procedures like angioplasty, often necessitating further medical intervention.

Pharmaceutical Eluting Stents

A drug-eluting stent is a stent coated with medication that is slowly released to prevent the re-narrowing of arteries.

Chorioallantoic Membrane (CAM) Assay

The CAM assay is an experimental technique used to study angiogenesis by observing blood vessel growth in chick embryos. It was utilized in this case to assess Taxol's anti-angiogenic properties.

Conclusion

The Conor Medsystems Inc v. Angiotech Pharmaceuticals Inc & Ors case serves as a cornerstone in the realm of patent law, particularly concerning the assessment of obviousness and the inventive step. By upholding the patent despite challenges based on the "obvious to try" doctrine, the House of Lords reinforced the necessity for a clear and substantiated inventive step beyond mere experimentation.

This judgment underscores the delicate balance patent law must maintain between fostering innovation through robust protection and preventing the monopolization of solutions that are readily apparent to experts in the field. The case sets a notable precedent, guiding future patent applications and litigation towards a more rigorous evaluation of what constitutes genuine innovation.