European Patent Law for US patent attorneys - Part 1

Although patent law is passingly similar across the world, there are some significant differences which can catch the unwary out. We are often asked about how US attorneys can make their patent applications ‘EPO-proof’ when drafted. With this in mind, we are publishing a series of three blogs on how US attorneys can better prepare their patent applications for Europe. The three parts are:

  • Part 1 - general preparation for European prosecution;

  • Part 2 - software patents; and,

  • Part 3 - medical device patents.

This is part 1.

General preparation for European prosecution

The following sections provide guidance on the most common pitfalls for US attorneys when prosecuting before the EPO (and the UK-IPO to some extent). Most are on the dreaded subject of “added matter”, but we have included a couple of other tips to ease the pain.

Added matter problems

Added matter is probably the most contentious topic at the EPO. Fundamentally, it is impermissible to add to a European application subject-matter which the skilled person cannot derive directly and unambiguously, using common general knowledge and also taking into account any features implicit to a person skilled in the art in what is expressly mentioned in the document, from the disclosure of the application as filed (see the Guidelines). The EPO take this very seriously, and the examiners can be somewhat over-enthusiastic when applying the law.

The good kind of “added matter”

The good kind of “added matter”


Avoiding intermediate generalisation rejections

Intermediate generalisation objections are probably the most common problem we encounter when instructed by US attorneys. An intermediate generalisation may occur in a number of situations, but two examples are:

  1. Limiting claim 1 to feature A when feature A is only disclosed in combination with feature B (A+B) in the application as filed; and,

  2. Limiting claim 1 to a broader (i.e. intermediate) generic feature (e.g. resilient member) when only one narrow example is provided in the applicaiton as filed (e.g. steel compression spring).

Although such objections are not insurmountable, at the very least the European attorney will need to spend time, effort and money construcing an argument as to why the skilled person would understand that what is now claimed was ‘clearly and unambiguously’ disclosed in the application as filed. Therefore it’s preferable to try and head these objections off at the pass.

This can be done at the drafting stage by making it clear that each important feature can be isolated from the others. Even if the drafting attorney does not want to put such intermediate positions in the claims, they can be included in the statements of invention.

Simialrly, trying to use intermediate language in the description can be very useful. So, for example, instead of saying ‘Figure 1 shows a steel compression spring 100’, one could say ‘Figure 1 shows a resilient member in the form of a steel compression spring 100’. This can be gold dust during European prosecution!

Providing basis for multiple dependent claims

We have freedom to pursue multiple dependent claims in Europe, and from experience this can be very useful in patent enforcement. It allows the patentee to choose from a far greater ‘menu’ of claims to be asserted against infringers. Therefore there is no doubt that multiple dependent claims are a useful thing for a patentee to have at his or her disposal.

With this in mind we recommend that basis for multiple dependent claims is provided in the statements of invention and / or description. This may be through the use of statements of invention for dependent claims (e.g. feature A may be provided in combination of any of the preceding features) or via a supplementary set of claims which may appear at the end of the description. Whatever route is chosen, it needs to be clear and unambiguous to the skilled addressee that the claimed features can be combined with various other combinations of features.

Providing basis for means + function

We know that US attorneys avoid means + function claim limitations (such as “means for illuminating”) like the plague. With US file wrapper estoppel we understand why! That said, these limitations are perfectly fine in Europe, and although not always necessary can provide a neat way of providing a nice, broad claim.

Therefore our advice is to provided basis for these features in the statements of invention or description, which gives us the option to use them in Europe if we need to.

Avoiding excess claims fees

EPO claims fees are pretty hefty. Claim 16 and above will set you back EUR235, and claim 51 and above EUR585. Therefore it benefits the applicant to keep the number of claims above 15 to an absolute minimum.

More than 15 claims in Europe will see you parting with a lot of these.

More than 15 claims in Europe will see you parting with a lot of these.


There are a number of ways of keeping those claim numbers down whilst retaining as much subject-matter in the claims as possible:

  1. Use multiple dependency. This can open up a lot more combinations in fewer claims, so well worth thinking about.

  2. Use “or” claims. When you have several alternatives, why not combine them into a single claim?

  3. Only use one independent claim per category. We will go into more detail below, but typically the EPO will reject multiple independent claims in the same category whether or not they have unity. Therefore try and avoid this else you may end up paying excess claims fees for no reason.

Avoiding multiple independent claim rejections

The EPO hate multiple independent claims in the same category (apparatus, method etc). Contrary to popular belief, this is not about unity of invention. Even if two independent apparatus claims (for example) have unity, the EPO can (and probably will) object on the basis of clarity. Over the past few years the EPO have made the rules around multiple independent claims to the extent that they may refuse to search the second independent claim, and ultimately force the applicant to excise it from the application altogether.


We advise that any claim set having more than one independent claim in a category is carefully reviewed and restructured to meet the EPO rules. This is not usually onerous, but will save a lot of time and energy later on in the process.

It is worth noting that there are a set of (limited) circumstances under which the EPO will allow multiple independent claims in the same category, which are:

(a) a plurality of interrelated products,

(b) different uses of a product or apparatus,

(c) alternative solutions to a particular problem, where it is inappropriate to cover these alternatives by a single claim.

These exclusions are construed pretty narrowly, and we recommend care is taken when relying on them.


Hopefully this will be of use - Vault IP are always ready to provide advice to any US attorney who is looking to draft an application for eventual European prosecution. Several of our clients will come to us for such guidance at the drafting and PCT filing stages. So if you have any questions, get in touch at or on +44 (0) 121 296 9164.