Germany: Reach-Through and Experimental Use: Some Remarks on the Situation in Germany

Last Updated: 23 October 2001
Article by Bernhard Fischer

Among all questions on how far patent protection should reach in the field of biotechnological inventions, controversies arising in context with granting, enforcing and licensing of patents on research tools remain an important point of discussion in practice. In that respect, the so-called "reach-through" problem was discussed following inventions on basic research tools (e.g. the PCR and Taq polymerase technology), and since then has been addressed on many occasions.

The term "reach-through" (which is not a term of art in patent law) is typically used for describing situations where the owner of a patent covering a research tool wants to know in how far he may assert the patent, and under which terms he may license the patent against a party which has developed or which is supposed to develop a downstream product by using the research tool. As a typical example for a research tool, one may take a receptor and use it in a method to screen for certain compounds that have an effect on the receptor. As a "downstream product", one may consider, with this example, a compound identified by the use of the receptor (i.e. an "intermediate downstream product"), and a pharmaceutical composition or medicament subsequently developed which comprises, as an active ingredient, the identified compound (i.e. a "final downstream product").

There are typically no profits made during the phase when the research tool is used for identifying / developing a downstream product. For this reason, the inventor of a research tool may not only want to know how probable it is whether he will be able to prevent a third party from using the patented research tool, but he may further have an interest in obtaining a share (in terms of damages or royalties) in the profits subsequently made with the developed downstream product. In contrast, the user of the research tool, who may have invested substantial time and money for developing and marketing the downstream product, has an interest in avoiding such a share and being sued as an infringer.

For further analysis of the above, a distinction is to be made between different infringement situations that are imaginable with a patent covering a research tool. Naturally, in an infringement case, damages can only be obtained if an infringement is thinkable. Considering different infringement situations, one needs to take into account the question in how far the use of a patent covering a research tool and/or potential downstream products may be exempted from patent infringement under the experimental use exemption. Here, an important development (not specifically dealing with "reach-through" situations, but potentially also relevant for such situations) has taken place in German case law on the experimental use exemption.

Finally, a basic distinction between different infringement situations also serves as a starting-point for further evaluating in how far royalties can be obtained as a share in profits made with a downstream product. The latter question which leads into issues of antitrust law, cannot be discussed in depth in the present article.

1. Infringement analysis for typical "reach-through" situations

When analysing a "reach-through" situation, one may distinguish a "research phase", i.e. a phase of using a patented research tool for identifying a potential intermediate downstream product, and a "marketing phase", i.e. a phase of developing and marketing a (final) downstream product. Typically, by the time of commercialisation of the downstream product, the research tool is no longer required.

1.1. Research phase: Verifying the functioning of a research tool versus taking its claimed function as granted

A third party starting research with a patented research tool, in the phase before actually identifying a potential intermediate downstream product, might try to invoke the experimental use exemption as a defence against an alleged infringement.

As one of the most classic reasons for invoking the experimental use exemption, the user of the research tool could state, for instance, that he is just verifying the functioning of the patented research tool. Moreover, following the development of German case law on the experimental use exemption (cp. Decisions Clinical Trials I of 1995 and Clinical Trials II of 1997 of the German Federal Supreme Court), according to which experimental use acts may even have a commercial purpose in view, a third party may be allowed to "test" a research tool for finding out whether it may be at all profitable to use it for its own business, and, in the affirmative, whether it is worthwhile to seek for a license.

On the other hand, the experimental use exemption would no longer apply when the research tool is used in a way which is taking its claimed function as granted, in order to develop a result that can typically be achieved by conducting research with the tool. In this case, the research acts performed with the tool would no longer relate to the subject matter of the invention, as required by established statutory law on the experimental use exemption. Regarding this criterion, an earlier Decision of the Berlin District Court of 1984 can be cited (Klinischer Test; rendered under the old German Patent Act of 1968), where the Court basically distinguished between experiments on the invention and experiments with the invention - the latter not relating to the subject matter of the invention.

In case of a research tool, a line between verifying its functioning and taking its claimed function as granted seems artificial and difficult to draw. In any case, it should be clear that one may not conclude from the intrinsic purpose of a research tool that the use of such a tool automatically amounts to an experimental use act in the legal sense. Rather, it should be hard to believe that a party using a patented research tool to a certain extent just uses it, for instance, for verifying its functioning or for testing its economic value. In practice, the problem is rather how to prove that a patented research tool is being used at all by another party and to which extent, if one wants to sufficiently establish acts of infringement.

1.2. Marketing phase of the downstream product

Time-consuming and expensive investigation is usually necessary for developing and marketing a final downstream product comprising a compound potentially obtained by the use of a patented research tool.

If the research tool is claimed in the form of a method claim, one may think that the downstream product can be considered as a product directly obtained by the claimed method (see Art. 64 (2) EPC) and, thus, amounts to an infringement. However, this may be difficult to establish:

For instance, in the example of a screening method with a receptor, a compound identified by the use of the screening method would only be an intermediate product subsequently manufactured into a different end product (a pharmaceutical composition or medicament), i.e. the final downstream product. Regarding the intermediate downstream product, it seems already questionable whether this may be considered as directly obtained by the research tool (i.e. the claimed screening method), since the research tool is only to identify such a product. Here, one may also take into account that the research tool is no longer required once the intermediate downstream product has actually been identified. Regarding the final downstream product, this may even less be considered as a product directly obtained by the research tool because considerable supplementary steps (potentially comprising modifications) are usually necessary for developing, manufacturing and marketing the final downstream product.

For the above reasons it is understandable that inventors of a research tool are seeking (beyond a patent claim on the research tool as such) either additional claims covering, to the widest extent, potential compounds that may be obtained by use of the research tool, or additional claim language which covers methods for the production of a pharmaceutical composition comprising such compounds. Under the current practice of the EPO, the former type of claims is likely to be rejected for lack of reproducibility, clarity and novelty; for the latter type of claim language, it remains to be seen whether it will be accepted by the responsible patent authorities.

If it was nevertheless possible to include such additional claims or claim language, the experimental use exemption would need to be reconsidered under different premises. In such circumstance, a party using the research tool for identifying a compound, or using it for a later development of a pharmaceutical composition comprising such a compound, could state that these are experiments relating to the subject matter of the invention, since the patent claims would explicitly relate to such compounds or to such compositions. In such a situation, the consideration that one should not conclude from the intrinsic purpose of a research tool that the use of such a tool automatically amounts to an experimental use act might not help, as opposed to the situation described in 1.1.

Further, under the ruling of the German Federal Supreme Court in its Decisions Clinical Trials I of 1995 and Clinical Trials II of 1997, the experimental use exemption probably even applies (within certain limits) when a pharmaceutical composition or medicament comprising the identified compound as an active ingredient has been developed, and when that pharmaceutical composition or medicament is tested, subsequently, in vitro, in animal tests and/or in clinical trials, with the goal to obtain regulatory approval for the developed composition.

2. Conclusion

It seems that under the current legal situation, the inventor of a research tool is somewhat in a trap: Given that it is currently not possible to include in a patent on a research tool a claim language that covers potential compounds or compositions to be identified/developed with use of the tool, the patent owner is not in a position to assert infringement regarding the marketing of a downstream product. On the other hand, if it is actually possible to include such a claim language, the experimental use exemption will possibly apply and even extend to clinical trials conducted with a developed downstream product with the goal to obtain regulatory approval.

Notwithstanding the above, a patent on a research tool certainly remains a powerful weapon which, by means of an injunction, can be used in a way to prevent third parties from having access to valuable research assets, and the experimental use exemption should not stand in the way as long as an infringer uses the tool for its claimed purpose by taking its functioning as granted. Finally, although the patent owner may not prevent the marketing of a downstream product, it is not completely excluded (and needs to be considered under the circumstances of each specific case, mostly under antitrust considerations) that damages may be requested on a "reasonable royalty basis" taking into account profits made with a downstream product.

© 2001 Bernhard Fischer.

First published with MIP (IP Strategy Yearbook 2001), Euromoney, London, 2001

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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