High Court Ruling: Patent Claims Invalid for Added Matter Despite Essentiality to UMTS Uplink DRX

Introduction

In the case of Conversant Wireless Licensing SARL v. Huawei Technologies Co., Ltd & Ors ([2019] EWHC 1687 (Pat)), the England and Wales High Court's Patents Court dealt with a complex dispute surrounding the essentiality and validity of a European patent held by Conversant. The central issue revolved around whether Huawei's mobile devices infringed upon Conversant's patent related to Universal Mobile Telecommunications Standard (UMTS) technology, specifically concerning Uplink Discontinuous Reception (Uplink DRX) mechanisms.

Conversant asserted that its patent, held under the FRAND (Fair, Reasonable, and Non-Discriminatory) licensing framework, was indispensable for implementing Uplink DRX in UMTS systems. Conversely, Huawei contested the essentiality of the patent and sought its revocation on grounds including added matter, obviousness, and insufficiency.

Summary of the Judgment

The High Court concluded that:

• The patent in question is essential to Huawei's implementation of Uplink DRX in UMTS technology.
• Despite this essentiality, the court found the granted claims of the patent invalid due to the addition of matter not originally disclosed in the application, specifically concerning the method of checking whether the medium access control (MAC) entity is transmitting in the current transmission time interval (TTI).
• The court also determined that the claims were not obvious in light of prior art, including Samsung's document and a US patent application by Terry.
• The claims were not found to be insufficiently disclosed.

As a result, while the patent was essential, its invalidity for added matter meant that Huawei did not infringe upon it.

Analysis

Precedents Cited

The judgment referenced several key precedents and patent law principles:

• Actavis UK Ltd v Eli Lilly & Co [2017] UKSC 48: Established the doctrine of equivalents, allowing for infringement findings even when claim language does not match exactly but the essence of the invention is replicated.
• Nokia Corp v IPCom GmbH & Co KG [2012] EWCA Civ 567: Clarified the strict approach towards added matter, emphasizing that claims must not extend beyond the original disclosure.
• AP Racing Ltd v Alcon Components Ltd [2014] EWCA Civ 40: Explained that added matter involves introducing new information not disclosed in the application as filed.

These references reinforced the court’s adherence to established patent law doctrines, ensuring that patents are not unjustly broadened during prosecution through claim amendments.

Legal Reasoning

The court's rationale centered on the principles of patent validity, particularly focusing on the "added matter" ground. Added matter occurs when a patent claim includes information that was not explicitly or implicitly disclosed in the original application. The key points in the reasoning were:

• Claim Construction: The court carefully construed the language of the patent claims, determining that the method involved checking whether the MAC entity could empty the radio link control (RLC) buffer in the current TTI to decide on transmitting data packets.
• Disclosure Analysis: Comparing the original application to the granted patent, the court identified that the specific check as claimed—determining transmission status by whether the MAC could empty the RLC buffer in the current TTI—was not clearly and unambiguously disclosed in the application.
• Doctrine of Equivalence: While Conversant attempted to argue infringement under the doctrine of equivalents, the court found that the added matter in the claims overshadowed any such considerations, rendering the claims invalid.
• Prior Art Consideration: The court examined prior art references, including Samsung's document and Terry's patent application, concluding that they did not render the patent claims obvious.

The court emphasized that even if a patent claim is essential to a technology, it must still meet all validity criteria, including freedom from added matter. The intentional or inadvertent expansion of claim scope beyond the original disclosure is not permissible.

Impact

This judgment underscores the critical importance of maintaining strict adherence to the original patent application during prosecution. It highlights that:

• Essentiality vs. Validity: A patent can be essential to a technology without qualifying as valid if it fails to meet all patentability requirements.
• Claim Amendments: Amendments to patent claims must not introduce new information that wasn't disclosed in the application as filed. This restrains patentees from broadening their claims post-filing unconsciously or deliberately.
• Infringement Determinations: Parties must ensure that patent claims are both essential and valid to successfully claim infringement, as invalid patents provide no enforceable rights.

For practitioners, this case serves as a cautionary tale to meticulously review claim amendments and ensure they remain within the bounds of the original disclosure. For patentees, it emphasizes the necessity of precise and comprehensive initial applications.

Complex Concepts Simplified

FRAND Undertaking

FRAND stands for Fair, Reasonable, and Non-Discriminatory. It is an undertaking by a patent holder to license their patented technology on terms that are fair and reasonable and without discrimination among different licensees. This ensures that essential patent rights are accessible to all parties needing them, promoting innovation and competition.

Essentiality of a Patent

A patent is considered essential to a technology if it covers aspects that are indispensable for implementing that technology. For instance, if UMTS Uplink DRX cannot function without infringing upon Conversant’s patent, then the patent is deemed essential.

Added Matter

Added matter refers to introducing new information into the claims of a patent that was not originally disclosed in the application as filed. This is not allowed as it can unfairly extend the scope of the patent beyond what was initially presented, potentially alienating competitors and stifling innovation.

Doctrine of Equivalents

The Doctrine of Equivalents allows a court to find patent infringement even when the accused product or process does not literally fall within the express terms of a patent claim but nevertheless performs substantially the same function in substantially the same way to achieve the same result. However, this doctrine cannot be used to cover added matter.

Conclusion

The High Court's decision in Conversant Wireless Licensing SARL v. Huawei Technologies Co., Ltd & Ors serves as a pivotal reminder of the delicate balance between patent protection and the boundaries of disclosure. While Conversant's patent was deemed essential for implementing Uplink DRX in UMTS technology—a significant endorsement of its technological relevance—the simultaneous invalidation of its claims for added matter underscores the paramount importance of maintaining fidelity to original disclosures during patent prosecution.