Interdigital Technology Corporation v Lenovo Group Limited

Patent claims are construed objectively and purposively, by asking what the skilled person would understand the claim language to mean in the context of the technical teaching.

A technical shorthand such as “MAC-d flow data” may include headers necessarily added during multiplexing where excluding them would defeat the invention’s purpose and produce an absurd result. “Smaller than” may mean the largest supported transport format that accommodates, but does not exceed, the relevant data. “Means for” language in an apparatus claim does not require the means to operate continuously.

Anticipation may arise where prior-art apparatus has means capable of producing the claimed result, even if it achieves that result only in particular operating circumstances.

The claimants alleged that EP 3 355 537 B1, concerning MAC multiplexing and transport-format selection in HSUPA, was essential to the UMTS Release 6 standard and infringed by Lenovo devices.

Lenovo disputed construction, essentiality and infringement, and challenged validity principally on anticipation and obviousness over Filiatrault, a marked-up version of TS 25.309 v6.2.0. The central issues were the meaning of “MAC-d flow data”, “smaller than” and “means for”, and whether Filiatrault disclosed or rendered obvious the claimed multiplexing process.

1. Construction. Applying the ordinary purposive approach identified in Eli Lilly v Actavis UK Ltd [2017] UKSC 48 and Icescape Ltd v Ice-World International BV [2018] EWCA 2219, “MAC-d flow data” included the necessary MAC headers and control information added during multiplexing. Excluding them would make the claim technically irrational, increase padding and defeat the patent’s stated purpose.
2. “Smaller than” meant the largest supported E-TFC which could accommodate, but did not exceed, the relevant data. The matching E-TFC was therefore included. A literal exclusion of an exactly matching E-TFC would reduce throughput and increase padding contrary to the teaching of the patent.
3. “Means for limiting” did not require continuous operation. The apparatus infringed if it possessed means capable of producing the specified result, even though those means operated only in some transmission circumstances.
4. Filiatrault. The document did not generally disclose the claimed additional selection step or treat the serving and non-scheduled grants as a combined absolute limit on the total resources used. The alleged common general knowledge could not be selected retrospectively to supplement an incomplete anticipation case. The relevant grants operated at MAC-e level and did not include padding.
5. The principal anticipation and obviousness arguments therefore failed. The court rejected the asserted “round down” reading as hindsight-driven and unsupported by the document as read by the skilled person.
6. However, DXX/14 demonstrated a particular operating scenario in which Filiatrault’s means produced the result required by integer 1F. Since the claim was expressed in broad “means for” terms, that was sufficient for anticipation. The patent was consequently invalid and could not be infringed or essential to the Standard.

First-instance decision of the High Court (Patents Court). No appellate history is stated in the judgment.