Biotechnological research involves the use of highly technical equipment. Research tools are products whose target market is researchers. A Harvard mouse retails for about fifty US dollars.102 It is important that an experimental use exception is not made wide enough to interfere with the supply of innovative research tools. It is difficult to justify a research exemption where the researcher is an ordinary consumer of an invention. Patents on the tools of basic research are unlikely to lock up areas of research. The patent holder can only gain the benefits of the patent by supplying the invention to as wide a market as possible. Therefore, there is an incentive to make the invention available to researchers. The issue of the patentability of expressed sequence tags (ESTs) brings into focus the problems surrounding patented research tools. ESTs are tiny fragments of genes. In any given cell, the active genes will be transcribed into messenger RNA which is then translated into a protein. ESTs are obtained by converting messenger RNA into complementary DNA (cDNA) and therefore share homology with those genes in a cell which are active, but the ESTs do not contain introns (noncoding regions). The function of the full gene from which these fragments are derived may be unknown.
The industrial application of ESTs is their use as molecular probes in finding full length sequences. Pieces of DNA (sequence information) including ESTs, for which no function is known, are more like pieces of information than new and useful chemical molecules. It has been suggested that because the utility of these molecules is so limited, patent claims to ESTs should be limited to the EST alone and not include longer sequences.103 The argument for a narrow scope for such claims is that further research on the full length gene may be hindered by a patent on an EST. The social contract basis of the patent system also suggests that a patentee who has identified only an EST has given consideration only for exclusive rights in the EST. Exclusive rights in a full gene should only be awarded for a disclosure of the function of that gene. If a patent on an EST also claims the full length gene sequence, other research teams may not be able to continue work on finding and understanding the function and regulation of that gene without a licence from the patent holder.
ESTs are useful for isolating full-length genes, locating coding regions on genomic DNA and identifying patterns of expression in different tissues.104 The development of commercial products, such as therapeutic proteins or genetic diagnostic tests, is likely to require the use of multiple gene fragments. This requirement is likely because biological systems use many regulatory mechanisms with overlapping functions. An example is the regulatory receptor gene families. The adrenergic receptor occurs frequently in the human genome, and may perform a different function in different tissues. The term adrenergic receptor occurs in the claims of over 100 issued patents in the United States.105 This means that a researcher wishing to learn about the effects of new therapeutic agents that exhibit adrenergic activity may have to negotiate over 100 separate licence agreements. It is asserted that the burden of arranging these licences can be a strong disincentive to undertake such research. Product development may also be hindered where patents on individual fragments of upstream research are held by different owners. Costly transactions may be required to bundle licences together before a firm can have the necessary materials for product development.106
ESTs as experimental tools raise interesting questions for patent law. As the only use of ESTs is as research tools for research into the full length gene from which they are derived, do they fall within the scope of the research exclusion to patent infringement? Does use of a sequence in electronic searching of databases constitute infringing use? Patent claims concerning ESTs generally claim not only the sequence of the EST but also claim DNA molecules that comprise the DNA sequence of the particular EST.107 This means that any DNA sequence that includes the EST sequence will fall within the scope of the patent. The decision of the House of Lords in Biogen108 may suggest that claims to a full-length gene sequence based on the invention of an EST would be invalid on the ground of insufficiency. A claim may exceed the technical contribution to the art by claiming every way of achieving a result when it enables only one way.109 An EST offers one way of obtaining the full gene sequence, but there may be other ways of doing so that owe nothing to the disclosure of the EST.
The argument against patenting of ESTs is that they may ultimately have a greater value than at present once the function of the genes from which they derive is discovered. It would seem to be unfair to grant patent rights in a gene to the person who first isolated an EST derived from that gene to the exclusion of the person who elucidates the function of the full gene. The disclosure of an EST in the context of the current state of the art generally would enable the location of the full gene to be found. However, without the disclosure of a function for the gene, the advance in knowledge will not be capable of industrial application.
The obvious question
There is some uncertainty regarding the tests used to determine the question of obviousness. This uncertainty could have been eased by a definitive statement on the nature of an inventive step from the House of Lords in Biogen.110 The decision, in that forum, that Biogen's patent was invalid was made on the ground of insufficiency, but Lord Hoffmann did make a potentially very useful observation on the question of inventive step. This observation was that the identification of the inventive concept is critical. In particular, the use of general language will tend to cast the inventive step too widely when the actual contribution to the art may be quite specific:
A proper statement of the inventive concept needs to include some express or implied reference to the problem which it required invention to overcome.111
The key is to state the invention at the right level of abstraction; if too general it may be considered obvious. The same level of abstraction must be seen in the scope of the claims. Where the claim states the invention too generally, it is likely to exceed the ground for a monopoly that is warranted by the actual contribution made.
It has been suggested there are two ways in which something can be non-obvious.112 First, a solution to a problem may involve some lateral thought because the step does not follow linearly, or logically, from an understanding of the prior art. Secondly, the solution may be the end result of a sequence of logical steps to be taken from the point at which the prior art had placed the skilled addressee:
The citadel may be captured either by a brilliant coup de main or by a slow laborious approach by sap and mine according to the rules of the art; the reward is the same.113
This raises the question of how important the route taken by the inventor is to the inventive step inquiry? An objective approach to inventiveness would tend to focus on the final result, involving a comparison between the invention and the prior art. A subjective approach places more emphasis on the route taken by the inventor. It is suggested that too great an emphasis on either approach leads to difficulties, and that the idea of the patent social contract can be employed to help define the inventive step.