T 0128/82 - Inventive step of product claims

Key points

• This is a decision from the archives.
• Let's assume a patent with a single claim directed to a single compound X. The claim is a pure compound claim, simply reciting the chemical formula (or IUPAC name), nothing more. The description teaches one possible use of compound X. Let's assume as a catalyst for some chemical reaction A.
• The claim is, however, not limited to that particular use. In fact, the claim gives absolute product protection, also covering other uses. For instance, as a catalyst for another chemical reaction B for which compound X may be a poor catalyst. Can an opponent use this in some way for an inventive step under current EPO case law, e.g. by filing evidence that compound X is not effective as a catalyst for chemical reaction B (assuming that chemical reactions B and A are very different from each other)?
• Decision T 0128/82 appears to indicate that such an attack does not work under the case law of the BoA.
• The decision is about first medical use claims, but that should not distract us now.
• The Board in T0128/82: "the practice of the European Patent Office hitherto has shown that substance and medical preparation claims for therapeutically active compounds not limited to specific indications are allowed, even though as a rule only certain specific activities are stipulated. " 
• So, to rephrase: the practice of the EPO then was [and still is] that product claims for compounds having some medical activity are allowed, these claims not being limited to specific uses, even though, as a rule, only one or few specific medical uses are taught in the description.
• As far as I know, the above statement is still the EPO's practice, and equally in non-medical fields of chemistry. Hence, the practice of the EPO is that product (substance, composition) claims are allowed, these claims affording absolute product protection not limited to a specific use, even though, as a rule, only one or few uses of the product are taught in the description.
• The relevant national German decision is Disiloxan, BGHZ 51, 378 (1969) on p.8, which indicates that the Kongorot decision of 20.03.1889 is to be followed (that decision can be found in Patentblatt 1889, issue 19, page 209, available at the DPMA website here. ).
• Also relevant is T 181/82, about the inventive step of a pure compound claim, which states that "An effect which may be said to be unexpected can be regarded as an indication of inventive step", the effect at issue was obtained when the claimed compounds were used as light stabilisers as was taught in the description.
• In other words, no patentability objection can be raised solely on the ground that a product claim covers any use whereas the description teaches only one use.
• Absolute product protection has been controversial in the past, somewhat recently for genes, and further back in history for chemical compounds in general. See, generally, R. Uhrich, Stoffschutz, 2010, available open access since 2020 under DOI 10.1628/978-3-16-159918-7.  The thesis is quite critical of the current case law on patents for chemical products.

The link to the decision is provided after the jump, as well as (an extract of) the text of the decision.

https://www.epo.org/law-practice/case-law-appeals/recent/t820128ep1.html

10. Whatever the case may be, the practice of the European Patent Office hitherto has shown that substance and medical preparation claims for therapeutically active compounds not limited to specific indications are allowed, even though as a rule only certain specific activities are stipulated. This practice usually always concerns new compounds. It does not derive from the Convention that compounds which although previously known are still patentable under Article 54(5) are in principle to be treated differently. If an inventor is granted absolute protection in respect of a new chemical compound for use in therapy, the principle of equal treatment would require that an inventor who for the first time makes a known compound available for therapy should be correspondinlyg rewarded for his service with a purpose-limited substance claim under Article 54(5) EPC to cover the whole field of therapy. Any other treatment would only be justified were Article 54(5) EPC absolutely to forbid a broad protective scope. The fact that Article 54(5) EPC does not contain any requirement that protection should be broad is of itself no reason for refusing to grant such protection. As a general rule the usual practice as it relates to new compounds should be followed.