EBA to consider claim construction questions in heat-not-burn dispute

Proceedings before the EPO Technical Boards of Appeal (BoA) between patent holder Philip Morris and opponent Yunnan Tobacco over a heat-not-burn patent have ended in a request for a referral (case ID: 439/22).

The technical board 3.2.01 under chairman Giovanni Pricolo  has confirmed that it seeks clarification regarding whether an examiner can use the content in a patent description to interpret the patent’s claims. It also keen to ensure uniform application of the BoA law and address potential divergence with national case law.

The Enlarged Board of Appeal (EBA) should confirm if it has accepted the referral by 10 June 2024. In the meantime, the Unified Patent Court has also weighed in on the issue.

Yunnan broaches claim construction

Yunnan Tobacco had opposed Philip Morris’ EP 3 076 804, a heat-not-burn patent which covers a ‘Heated aerosol-generating article with thermal spreading wrap’. During appeal proceedings, parties had focused on the question of understanding use of the term ‘gathered sheet’ in the relevant prior art. While opponent Yunnan argued that, to aid this, the examiners should consider the patent description as well the patent claims, Philip Morris favoured a narrower interpretation which considered only the claims.

Currently, the EPO’s Opposition Division is bound only to examine a patent’s claims and not its description. This is contrary to the approach of Europe’s national courts. However, no blanket approach yet exists, either across the EPO or across national jurisdictions.

Heat-not-burn issue paves way

For years, EPO examiners have held diverging views regarding the approach opposition divisions should take when examining a patent for validity. Some examiners state the need to take into account the description as well as the claims. On one hand, some divisions take a ‘dictionary’ approach where the reading of both the patent claims and description may see it lack novelty; on the other, some divisions take a ‘primacy’ approach, whereby just examining the claims is more likely to find them novel.

An example is the discrepancy between previous decision T 1473/19 involving Schleifring and Siemens Healthcare (2022) and decision T 169/20 involving Reckitt Benckiser Vanish and Henkel (2023). The latter board argues the description should only be taken into account in cases where urgent clarification on, for example, subject matter is needed, while T 1473/19 says an examiner should consider both equally.

In the current case, Philip Morris took a ‘primacy’ approach in its arguments. While the debate has raged among EPO boards for decades, this is the first time a board has referred a case which refers directly to this discrepancy to its highest appeal body.

Future consequences

Furthermore, claim interpretation is important for almost every case heard at the EPO Opposition Division. Thus, should the EBA accept the referral, it is highly likely that this will stay multiple opposition proceedings pending the EBA’s decision. Observers expect that any decision will not be forthcoming until late 2024 or early 2025 at the earliest.

Recently, the UPC has also weighed in on the debate. In the case between NanoString and 10X Genomics, its court of appeal decided that judges must consider the description and drawing in patent claims when assessing both infringement and validity (case ID: UPC_CoA_335/2023). Since a core aim of the UPC is to harmonise the approach to patent law across Europe, it is likely that all relevant EPO boards will take into consideration the recent UPC judgment in submitting and accepting the referral.

For Yunnan Tobacco
EP&C (Amsterdam): Marcel Kortekaas (partner); patent director: Thomas Remmerswaal (both patent attorneys)

For Philip Morris
HGF (Birmingham): Christopher Moore (partner); associate: Robert Walton (both patent attorneys)

EPO Boards of Appeal (Munich), Technical Board  3.2.01
Giovanni Pricolo (chairman); members: Peter Guntz, Vincenzo Vinci