By a landmark decision dated 25 November 2008, the Enlarged Board of Appeal of the European Patent Office (EPO) refused a patent application by Wisconsin Alumni Research Foundation (WARF) (the Appellant) covering the use of human embryonic stem cells (ESCs). Stem cells are a special type of precursor cell, capable of renewing themselves and differentiating into a diverse range of cell types from skin to nerve cells. While stem cells are found in adults, the early embryo consists of a sphere of particularly important stem cells called ESCs, which are capable of forming any cells of the body.

The patent application was held to be contrary to morality for the purposes of Article 53(a) of the European Patent Convention (EPC) and expressly excluded under Rule 28(c) (formerly 23d(c)) of the EPC Implementing Regulations as an invention concerning uses of human embryos for industrial or commercial purposes. This decision makes it clear that even if ESCs are not disclosed in the claims of the patent application, to the extent that the invention necessarily requires the use of human embryos as starting material, in the eyes of the EPO this is contrary to morality.

The European law applied was only adopted after ten years of controversy and difficult political negotiation. This decision to interpret the law widely means that the UK now finds itself in the unusual position that while certain research on human ESCs is permitted, innovative researchers are prevented from benefitting from the monopoly reward for investment that is available for other biotech research.


The Law

Article 53(a) of the EPC states that European patents shall not be granted in respect of inventions, the publication or exploitation of which would be contrary to "ordre public" or morality. Exploitations should not be deemed to be contrary however merely because it is prohibited by law or regulation in some or all of the Contracting States.

Rule 28 of the Implementing Regulations of the EPC states that under Article 53(a), European patents shall not be granted in respect of biotechnological inventions which, in particular, concern the following:

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

The Appeal

In 1995, WARF filed a patent application claiming a cell culture comprising primate ESCs with specific characteristics. The application was initially refused and the applicants appealed. On 3 March 2008 (Decision T 1374/04), the Technical Board of Appeal referred the following points of law to the Enlarged Board of Appeal:

  1. Does Rule 23d(c) [now 28(c)] EPC apply to an application filed before the entry into force of the Rule?
  2. If the answer to question 1 is yes, does Rule 23d(c) [now 28(c)] EPC forbid the patenting of claims directed to products (here: human 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?
  3. If the answer to question 1 or 2 is no, does Article 53(a) EPC forbid patenting such claims?
  4. In the context of questions 2 and 3, is it of relevance that after the filing date, the same product 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)?

The patent application in question was No. 96 903 521.1, which contained a set of claims 1 to 10 of which claim 1 reads:

  1. A cell culture comprising primate embryonic stem cells which (i) are capable of proliferation in vitro [sic] culture for over one year; (ii) maintain a karyotype in which all chromosomes normally characteristic of the primate species are present and are not noticeably altered through culture for over one year, (iii) maintain the potential to differentiate to derivatives of endoderm, mesoderm, and ectoderm tissues throughout the culture, and (iv) are prevented from differentiating when cultured on a fibroblast feeder layer.

The Examining Division originally refused the application for the reason that certain of the claims (including claim 1) did not comply with the requirements of Article 53(a) EPC in conjunction with Rule 23(d)(c) [now 28(c)] EPC because the use and destruction of human embryos was indispensible at the time of filing to produce the claimed embryonic stem cell cultures.

The Technical Board of Appeal considered the question of patentability of human ESCs as being an outstandingly important point of law (within the meaning of Article 112(1)(a) EPC) for which a decision by the Enlarged Board of Appeal was required.

The appellant's case

The appellant submitted an introductory comment stating that the named inventor using the methods suggested in the application was the first to successfully isolate and culture human ESCs that can grow in vitro. This was without doubt a major scientific breakthrough, opening up great potential for promising medical therapies. The appellant argued that it was therefore worthy of patent protection.

The appellant also submitted that the Enlarged Board of Appeal should ask for a ruling by the European Court of Justice (ECJ) on the interpretation of the relevant European Union Law under the Article 234 procedure. The appellant claimed that the Enlarged Board of Appeal was a court or tribunal for the purposes of the ECJ criteria.

Relating to question 1, the appellant accepted that Rule 28(c) of the EPC applied to pending European patent applications filed before it came into force.

Relating to questions 2 and 3, the appellant argued that the correct approach to Rule 28(c) was to identify the claimed monopoly and ask whether that monopoly embraces the "use of an embryo for an industrial or commercial purpose". Under this test, a claim to an embryonic stem cell was not a monopoly to "the use of an embryo" and still less to "the use of an embryo for an industrial or commercial purpose". Furthermore, on the basis that some Member States allow stem cell research on pre-14 day embryos, the appellant argued that there was no reason to forbid patenting of a use involving extracting some cells from such an embryo. The appellant argued that, if the legislation intended to exclude from patentability all products derived from human embryos, it would have explicitly said so. The appellant looked into the historical evolution of the relevant law and claimed that the wording finally used had been influenced by UK government submissions in order to allow such uses.

Relating to question 4, the appellant did not think it necessary to address this point given that it claimed the use of embryos in the present case was anyway outside the prohibition of Rule 28(c).


The Enlarged Board of Appeal declined to make a referral to the ECJ, commenting that neither the EPC nor the Implementing Regulations made any provision for a referral by any instance of the EPO of questions of law to the ECJ. The Boards of Appeal were a creation of the EPC, and their powers were limited to those given in the EPC. Such a referral was deemed to be impossible. Similarly, Article 234 of the EC Treaty did not appear to provide any basis for an EPO Board of Appeal to refer any questions before such Board of Appeal to the ECJ. Whilse EPO Boards of Appeal have been recognised in the past as courts or tribunals, they are not courts or tribunals of an EU Member State but of an international organisation whose contracting states are not all members of the EU.

Finally, Article 23(3) EPC provides that in their decisions, the members of the Boards of Appeal shall not be bound by any instructions and shall comply only with the provisions of the EPC. Even if a ruling of the ECJ were obtained, the Enlarged Board of Appeal did not have the power to bind itself to follow such a ruling.

The questions referred to the Enlarged Board of Appeal were answered as follows:

Question 1

Rule 28(c) applies to all pending applications including those filed before the entry into force of this rule.

The introduction of the new chapter into the EPC Implementing Regulations containing the relevant legislation did not contain any transitional provisions. This could only be taken as meaning that the detailed guidance on what was patentable and unpatentable was to be applied as a whole to all then pending applications. The appellant did not argue that Rule 28(c) EPC took away the possibility to patent anything which had previously been regarded as patentable under Article 53(a) and this was not the case.

Question 2

Rule 28(c) EPC forbids the patenting of claims directed to products 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, even if the said method is not part of the claims.

The relevant question was whether the present invention falls under the prohibition of Rule 28(c). The historical papers relating to the development of this provision showed clearly that the legislator's concern was to prevent a misuse in the sense that a commercialisation of human embryos. Neither the EU legislator nor the EPC legislator chose to define the term "embryo", despite being aware of the more restrictive definitions used in UK and German national laws. Given the purpose to protect human dignity and prevent the commercialisation of embryos, the Enlarged Board of Appeal could only presume that "embryo" was not to be given any restricted meaning.

While the use of human embryos did not appear in the claims of the patent, Rule 28(c) does not mention patent claims but rather refers to "invention" in the context of its exploitation. The technical teaching of the application as a whole had to be considered and the only teaching for making human embryonic stem cell cultures was the use (involving their destruction) of human embryos.

To restrict the application of Rule 28(c) EPC to what an applicant chooses explicitly to put in his claim would have the undesirable consequence of making avoidance of the prohibition merely a matter of clever and skilful drafting of such a claim. A claimed new and inventive product must first be made before it can be used. Such making is the ordinary way commercially to exploit the claimed invention and falls within the monopoly granted.

The Enlarged Board of Appeal was not persuaded by the argument that the wording of the legislation had been narrowed historically in accordance with submissions by the UK Government. Patentability was only to be considered if the invention was to the benefit of the embryo itself.

The Enlarged Board of Appeal's sole job was to interpret the legislation as intended and it was not necessary or appropriate to address arguments concerning the balance between the benefits of the invention for humanity and prejudice to the embryo.

Question 3

No answer is required since questions 1 and 2 have been answered with "yes".

Question 4

In the context of the answered question 2, it is not 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.

This could not be cured by the occurrence of subsequent technical developments. Any other conclusion would lead to legal uncertainty, and risk being to the detriment of any third party who later provided an innocuous way to carry out the invention.


When compared to other EU Member States, the UK takes a liberal approach to stem cell research. Licences are granted for research involving the destruction of early human embryos on the basis that stem cell research offers the best hope of potential cures for conditions such as Type 1 diabetes and Parkinson's disease.

Advocates argue that the early embryo is no more than a sphere of cells and that the 'leftover' embryos from IVF would be wasted in any event. Given the unique makeup of an ESC, there is not yet an adequate substitute. In the last few years, researchers have managed to produce stem cells with similar properties to ESCs, from adult body cells which may be able to differentiate into any cell type. Nonetheless, these cells are not the same as ESCs and the differences are not yet fully understood. Perhaps ironically, the production of these cells requires the insertion of genes found to be important in ESCs, which in turn would not have been possible without previous ESC research.

On the other side of the fence, opponents call such research immoral because it devalues human life. Such research is seen as the first stage on a slippery slope to designer babies and spare-parts clones.

The reason for the relevant EU legislation to this case was a desire to harmonise biotechnology law throughout Europe. The biotechnology industry was (and still is) viewed as a commercial sector poised for substantial growth in the 21st century and harmonisation is hoped to increase the global competitiveness of the single European market. The negotiation of the Directive on the Legal Protection of Biotechnological Inventions (incorporated into the EPC) was a long and difficult process, owing in part to the different ethical views taken by contracting states to issues such as stem cell research. Even once adopted in 1998, several countries took the best part of a decade to implement it into national law.

While the UK accepted Article 53(a) of the EPC and Rule 28(c) of the Implementing Regulations some time ago, the breadth of the EPO's interpretation of the prohibition will surprise many. The EPO has found it sufficient that ESCs were a necessary precursor to the technology detailed in the patent claims to find the technology unpatentable. The fact that an unpatentable invention is necessary to utilise the invention as set out in the claims of a patent does not normally prohibit a patentable invention as claimed. One example is the Swiss-type claim used for many years to allow patenting of second medical uses despite the fact that the substance is not novel and the method of treatment is excluded from patentability.

This judgment is likely to rule out patents which claim any technology relating to human ESCs. Critics of the decision will argue that this will disincentivise investment in critically important stem cell research. In the meantime, academic researchers will be breathing a sigh of relief as the WARF patent itself would have made the majority of ESC research subject to royalties. With the EPO refusing (and indeed saying it is unable to) refer these questions of interpretation to the ECJ, it looks like this decision will affect the direction of UK ESC research for years to come.