The (European) WARF Decision


G02/06 - the decision re patentablity of human embryonic stem cells in Europe

The WARF decision is out: the Enlarged Board of Appeal (EBA) has held that the WARF invention required, at the time of filing, destruction of an embryo. Whatever the claims covered, this inevitable embryo destruction meant the application had to be refused.

The Wisconsin Alumni Research Foundation (WARF) have thus had any hopes of obtaining European patent protection for their method for producing primate embryonic stem cells quashed. On 25th November 2008, the EBA of the European Patent Office (EPO) decided to finally reject their patent application [European patent application No. 96903512.1] on the grounds that it would be contrary to ordre public or morality under Article 53(a) of the European Patent Convention (EPC) to grant a patent for an invention that required the destruction of a human embryo.

WARF’s application, dating from 1985, embraced claims to human embryonic stem cells per se and was refused at Examining Division level on the ground that it contravened Rule 28(c) EPC 2000 [previously Rule 23d(c) EPC 1973], which excludes the uses of embryos for industrial or commercial purposes from patentability. WARF appealed and in Decision T 1374/04 the Technical Board of Appeal (TBA) referred the case and, specifically, certain points of law to the EBA. The particular rule at issue echoes, and has its origins in, Article 6(2)(c) of the European Union’s Biotechnology Directive [98/44/EC; ‘the Directive’], prompting WARF inter alia to request that the referred points be further referred to the European Court of Justice (ECJ).

Whether to refer to ECJ?

The EBA was clear: this case could not be referred to the ECJ. Their decision states ‘Neither the EPC nor the implementing regulations thereto make any provision for a referral by any instance of the EPO of questions of law to the ECJ’.

The Four Questions

The referral to the EBA was based on four questions, as recited in G 02/06, which are now discussed in turn.


Does rule 23d(c) apply to an application filed before entry into force of the rule?

Article 6(2)(c) of the Directive was implemented as Rule 28(c) EPC 2000 [previously Rule 23d(c) EPC 1973] on 1 September 1999. This raised the question of whether its specific exclusion of patents that involve the use of embryos for industrial or commercial purposes was retrospectively applicable to applications filed before this date, as was the case for the WARF application.

The EBA noted there were no transitional provisions. Hence the rule was seen as representing guidance on what is and is not patentable, with no suggestion that the rule has made unpatentable anything that was previously patentable. Specifically, there was no indication that hitherto the commercial exploitation of embryos was regarded as patentable.

In its submissions, WARF agreed, and so did the EPO President and most amicus curiae briefs. There seemed nothing more to say in relation to this question other than “Yes”.


If the answer to questions 1 is yes, does Rule 23d(c) [now 28(c)] EPC forbid the patenting of claims directed to products (here: embryonic stem cell cultures) which - as described in the application - at the filing date could be prepared exclusively by a method which necessarily involved the destruction of the human embryos from which the said products are derived, if the said method is not part of the claims?

The invention concerns primate embryonic stem cells, including human embryonic stem cell (hES) cells, which at the filing date had to be prepared from an embryo, said embryo being destroyed in the process.

Rule 28 EPC 2000 [previously Rule 23d EPC 1973] provides:-

"Under Article 53(a), European patents shall not be granted in respect of biotechnological inventions which, in particular, concern the following:

(a) ...

(b) ...

(c) uses of human embryos for industrial or commercial purposes;

(d) ..."

The question considered by the EBA was whether the invention falls within this provision. In interpreting the provision the EBA looked at the ordinary meaning to be given to the terms in context and in light of the object and purpose, including the preparatory documents of the Directive.

In the draft of 11 October 1997, the amended proposal for the Directive submitted by the Commission referred to ‘methods in which human embryos are used’, these methods being considered unpatentable. This was later revised on 26 February 1998 to read ‘uses of human embryos for industrial or commercial purposes’, which became the final text of the Directive and of Rule 28(c) EPC 2000 [previously Rule 23d(c) EPC 1973].

The straightforward reading of the words is that patenting is prohibited if a human embryo is used for industrial or commercial purposes. The EBA held this interpretation to be in line with the intention of the legislator, which was to avoid the commodification of human embryos, fulfilling the objective of the Directive to preserve human dignity.

This would appear on the surface to go against EC funding of research using human embryos. However, on page 7 of EC press release 11554/06 (Presse 215) of 24 July 2006, the Commission confirmed that it would continue to refuse to submit to the Regulatory Committee proposals for projects that necessarily involve the destruction of human embryos. The Commission also said in the same press release it would not be prevented from funding subsequent steps involving human embryonic stem cells. The Commission thus finds a distinction between funding for procedures to produce hES cells (not to be authorised) and funding for procedures that depend on the supply of hES cells from another source (“Ok, but don’t tell us where you got ‘em”).

It was argued that WARF’s claims do not specify a primary source of embryonic stem cells for further processing as being human embryos, which are necessarily destroyed in the process. Hence the claims do not require embryo destruction - could this enable allowance?

In its ruling, the EBA stated that the legislation refers to the whole invention not just to the claims. Before hES cell cultures are used, they have to be made and thus the teaching of the patent as a whole is relevant. The teaching of the patent requires destruction of the human embryo and this falls within the prohibition of Rule 28(c) EPC 2000.

The decision further commented that:-

“To restrict the application of Rule 28(c) (formerly Rule 23d(c)) EPC to what an applicant chooses explicitly to put in his claim would have the undesirable consequence of making avoidance of the patenting prohibition merely a matter of clever and skilful drafting of such claim.”

WARF also argued that the legislative history of the rule meant that the scope of the exclusion had narrowed over time, and should be read accordingly. However, the EBA highlighted that this apparent narrowing was merely a clarification to distinguish uses referred to by Rule 28(c) EPC 2000 from others uses, for example, those that impart a benefit to the embryo. It would be hard to argue that a process that necessarily destroys an embryo could be beneficial!

WARF put forward another argument against the applicability of Rule 28(c) and attempted to define an embryo as being at least 14 days old – hES cells can be obtained from younger embryos. The EBA found this failed as there is no indication that this definition was or is a universally accepted one. In fact some definitions, including those in UK and German Law, embrace embryos from conception onwards, including a fertilised egg.

Another line submitted by WARF was that obtaining a cell from an embryo in order to derive a stem cell line for research purposes was not an industrial or commercial act. The EBA rejected this.

The EBA held the legislators wanted to exclude inventions like the present one and in doing so have remained within the World Trade Organisation’s Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS), which sought to construct international rules for the protection of intellectual property. In this clear light there is no room for argument on questions such as the benefits of the invention for humanity, whether the benefits of the invention should be balanced against the prejudice to the embryo or at what point in time is morality to be judged (e.g. now or at the filing date?).

In conclusion, the answer is that the prohibition applies to the invention as a whole, not as defined in the claims, and that a patent is to be denied if carrying out the invention requires destruction of an embryo, regardless of the nature of the products obtained or claimed.


If the answer to question 1 or 2 is no does Article 53(a) EPC forbid patenting such claims?

The EBA decided no answer was needed: the EBA had held that Rule 28(c) EPC 2000 [formerly Rule 23d(c) EPC 1973] is applicable in the present case and so it follows that Article 53(a) EPC forbids patenting of products that at the time of filing could be prepared exclusively by a method that involves the destruction of human embryos.


In the context of questions 2 and 3, is it of relevance that after the filing date the same products could be obtained without having to recur to a method necessarily involving the destruction of human embryos (here: e.g. derivation from available human embryonic cell lines)?

At the time of filing, the only methods for isolating hES cells involved the destruction of the embryo. Since then hES cell lines have been deposited in stem cell banks and hES cells can be obtained and expanded from those deposits. In addition a technology has emerged that enables the production of cells with similar properties to hES cells (see Takahashi, K. and Yamanaka, S. Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell 126:663-676, 2006). So-called induced pluripotent stem (iPS) cells can be produced from less controversial fibroblast cells and could replace the need for the direct extraction of hES from embryos. The claims of the WARF application when taken together with iPS technology or cells from a stem cell bank enable the skilled person to fulfil the objectives of the invention without destroying a single embryo. This point was made by WARF.

In response, the EBA asserted that when assessing this rule, technical developments after the filing date can not be taken into account. Just as an invention which is insufficiently described cannot be rescued by subsequent technical developments neither can, in considering morality, the question of how the invention is required to be carried out. Any other conclusion would lead to legal uncertainty or be to the detriment of another who later comes up with an innocuous way of carrying out the invention. In this respect the decision emphasizes a fundamental cornerstone to the patent system: the absolute nature of the content of the specification as filed.

The EBA was careful to specify that the decision is not concerned with the patentability of stem cells per se, merely with the patentability of inventions which inevitably require the destruction of an embryo, whether product or process inventions.


In a landmark decision, the EPO has thus finally and clearly rejected the appeal for the grant of a patent for an invention the carrying out of which necessarily (at the time of filing) destroys a human embryo. In doing so it has set clear guidelines for future cases, namely:-

--- there is no provision in the EPC for referral to the ECJ from decisions of the TBA or EBA;

--- technical developments after the filing date can not be taken into account when assessing whether the application falls foul of the morality provisions of the EPC;

--- consideration of the invention as disclosed rather than as claimed is relevant for assessment of compliance with the EPC morality provisions;

--- making a product with the intention of further research constitutes industrial exploitation of the invention; and

--- the decision raises no objections to the patenting of human stem cells per se.

Role of the Patent Attorney

The comment of the EBA that skilful claim construction may be a dangerous thing to be guided by seems to go against the raison d’etre of patent attorneys, which is to find the right language to catch the desired claim scope whilst tiptoeing carefully around the prior art and complying with the requirement for a valid claim. But is there really no role for skilful claim drafting?

Consider the example of methods of diagnosis claims, which are not allowable under Article 53(a). These can be rendered allowable by the simple act of cutting out wording that includes as an essential feature of the claim that the method is carried out on the human or animal body, thus enabling valuable development of life-saving medical methods through the benefits of the patenting system.

We can e.g. compare the unallowable:-

“A method of diagnosis comprising extracting a tissue sample from a human body, subjecting the tissue sample to diagnosis procedure X...”

with the allowable:-

“A method of diagnosis comprising providing a tissue sample which has been extracted from a human body, subjecting the tissue sample to diagnosis procedure X...”

Is it not clearly the case that the totality of the diagnosis process must at some stage involve taking a sample from the human or animal body, thus requiring a step carried out on the human or animal body? Under the EPO case law the invention does not, as a whole, relate to a method carried out on the human or animal body because the invention as claimed does not relate to a method carried out on the human or animal body. It could be argued that the diagnostic method could be carried out on tissue samples from a bank or on blood samples in long term storage, but they must have come from someone originally, mustn’t they?

Deposit at the time of filing?

The decision begs the questions whether a deposit of a hES cell line under the Budapest Treaty in advance of the WARF filing would have helped – as others could have been directed to the cell line thus avoiding the need to destroy an(other) embryo to practice the invention. The answer seems to me that it might have made the key difference.

Effect of the decision on the industry

Already many observers have commentated on the impact of the decision. The consensus is growing: the law in Europe is clarified and future patent protection for methods and for human stem cells per se based upon cells obtained from deposited lines is relatively unaffected. If your current methodology does indeed use human embryos then make sure you include, on filing, disclosure of how to carry out the invention using cells from an acceptable source, such as a deposit.

Effect of the decision on pending applications

Given the comment that post-filed technical developments cannot be taken into account, it seems that pending applications are doomed or not dependent upon their original disclosure. Regardless of the product or method claimed, if the only means of carrying out the invention disclosed requires embryo destruction then the invention will be refused in Europe. Claims to e.g. purified cardiac stem cells will fail if these are obtained by differentiation of hES cells obtained in turn from an embryo. But if a source of cells is included other than an embryo, such as adult or even foetal cells, the problem seems to be avoided.

Relevance to iPS cells

The decision seems to open the door to patents on cells and methods relating to iPS cells or cells obtained from iPS cells – no embryos are destroyed using this technology.

What next?

EPO examiners will have been waiting to examine cases held up by this referral and we now await the avalanche of new examination reports. We think we know what ours will say.

Examiners at the UK IPO now have a new "Practice Note" to guide them. Following the WARF decision, this states that the UK IPO will still grant patents for inventions relating to human embryonic stem cells "provided that, at the filing or priority date, the invention could be obtained by a means other than the desctruction of human embryos".