Opposition At The European Patent Office

Any business that develops new products or processes runs

the risk of infringing third party patent rights, which can

result in the business being drawn into patent disputes. It is

therefore good business practice for companies to maintain a

regular watch on the patenting activities of at least their

main competitors. Where potentially relevant patents or patent

applications are found, strategies can be developed to reduce

this risk by designing around the patents, by challenging the

validity of the patent rights or by amicable business

resolution.

The European Patent Convention (EPC) provides an opposition

procedure which allows the validity of a granted European

patent to be challenged. The opposition must, however, be filed

with the European Patent Office (EPO) within nine months of the

grant of the European patent. The opposition procedure is a

consolidated process which allows a single challenge to be made

that is effective in all countries covered by the granted

patent. Third parties that are sued for infringement under a

European patent may also intervene in any existing opposition

proceedings provided they do so within three months of the

start of the infringement proceedings.

What challenges can be made

The European Patent can be challenged on the grounds that

the claimed invention is not patentable (for example it is not

new or not inventive); that the patent does not describe in

sufficient detail how the claimed invention can be carried out;

and/or that the granted patent contains new matter that has

been added since filing.

How to build a case

The strength of any opposition is only as good as the

evidence that is provided to support the grounds on which the

European Patent is challenged. It is therefore critical to

consider what contribution the patent claims to have made over

existing knowledge, and to assess whether this contribution

meets the patentability requirements set by the EPC. To make

this assessment, companies need to investigate and understand

what was publicly known before the effective filing date of the

patent. This will involve searching for earlier publications,

such as papers, journals and earlier patents and patent

applications. The EPO will itself have carried out a search for

such material, and in granting a patent will have concluded

that the claimed invention is patentable over the material it

found. You should however double-check this yourself, as the

EPO may have been misled by the proprietor.

Another useful source of material is the official files of

corresponding patent applications possibly filed in other

countries. The material found by other patent offices may be

more relevant than that found by the EPO. Consideration should

also be given to whether or not anybody (including the

proprietor) had publicly used the claimed invention prior to

the effective filing date of the patent. It is worth checking

the proprietor's sales and marketing material, since some

companies forget the need to file their patent application

before publishing the invention. With this knowledge it is then

possible to assess whether there is a case to be made that the

claimed invention is not patentable.

With regard to the other grounds, consideration should be

given to whether or not it is actually possible to carry out

the claimed invention...