In Yunnan Tobacco vs. Philip Morris, the EPO Boards of Appeal will refer key questions on claim construction to the EBA. If the EBA accepts the referral, which considers that both patent claims and patent description should be taken into account during examination, this could stay multiple opposition cases at the EPO.

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 EPO technical BoA 3.2.01 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 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 raises the subject of claim construction
Yunnan Tobacco had opposed Philip Morris’ European Patent EP 3 076 804, a heat-not-burn patent which covers a ‘Heated aerosol-generating article with thermal spreading wrap’. During appeal proceedings, the 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
EPO Examiners have for many years 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. Reading of both the patent claims and description may see the claims lack novelty, whereas just examining the claims is more likely to find them novel.

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

This is the first time a board has referred a case which refers directly to this discrepancy to its highest appeal body.

Future consequences
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 court of appeal decided that judges must consider the description and drawings in patent claims when assessing both infringement and validity ( NanoString v 10X Genomics; 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.