United States: Getting The Best Out Of The EPO During The International Phase Of A PCT Application For US Applicants

Many US applicants using the Patent Cooperation Treaty (PCT) system designate the European Patent Office (EPO) as the International Searching Authority (ISA) to conduct the international search in Chapter I of the PCT procedure.  This decision carries with it certain consequences during the international phase, and during the national and regional phases thereafter.  Nevertheless, used properly, selecting the EPO as ISA, and optionally International Preliminary Examination Authority (IPEA) can give US applicants significant benefits.

The EPO is one of the six patent offices available to U.S. applicants as ISA.  The benefits to US applicants in selecting the EPO as ISA include:

  1. a complimentary search, to that obtained via the US Patent and Trademark Office (USPTO), that often considers non-US prior art in more detail; 
  2. a search opinion that reflects the approach to patentability taken by the EPO and more in line with many patent offices outside the US; 
  3. an EPO search on all claims, without the need to pay extra fees for claims in excess of 15;
  4. an exemption from payment of the EPO search fee during the regional phase; and
  5. potentially faster prosecution during the EPO regional phase. 

Both (1) and (2) above are provided without limit on the number of claims and without the significant fees payable for more than 15 claims in an application filed at the EPO.  In addition, electing the EPO as IPEA also leads to a reduction of 50% in the EPO examination fee due during the regional phase. 

These benefits mean that a US applicant can proceed to the national phase of a PCT application with a more informed view on the likelihood of success in the EPO and other countries with similar laws, which in turn may help expedite prosecution.  However, US applicants should keep in mind the potentially less desirable consequences that come with these benefits, as discussed below.

The EPO approach to unity of invention

The EPO examiners take a strict approach to unity of invention and limit searching to only those claims that together have the same special technical feature underlying the invention.  This manifests itself in two ways:

  1. the assessment of multiple independent claims in the same category but defining different features as being claims to different inventions (a priori lack of unity); and
  2. the case in which a broader, linking claim is found to lack novelty and there are several dependent claims, each covering different technical features (a posteriori lack of unity).

Both of these approaches can have a particular impact where a US-style claim set, involving multiple independent claims, or single claim dependencies for equivalent features.  In both cases, the applicant will be invited to pay further search fees and failure to do so will result in: 1) no search being performed on the second and subsequent inventions, 2) a requirement to delete the unsearched claims during the EPO regional phase, and 3) an inability to amend to any of the unsearched claims that are not unitary with the searched claims.  

The EPO's refusal to search certain subject matter

Methods of doing business, and methods of medical treatment are not patentable in the EPO.  EPO examiners are therefore allowed to refuse to search claims directed to these subjects, if no obvious technical subject matter can be seen.  Furthermore, even if a search is performed, the excluded subject matter is not considered limiting, leading to claims being given a very broad interpretation which can lead to the search being less useful for understanding potential scope of protection. 

The requirement to respond to the PCT search opinion early in EPO prosecution

If the claims presented in the EPO regional phase are the same as those presented at the PCT search phase, the EPO will treat the PCT search opinion as an EPO search opinion.  Namely the EPO will require the applicant to responds to the matters raised when indicating the intent to proceed with the application.  The invitation to respond will closely follow entry into the EPO regional phase and require a response within six months. 

Actions to improve the outcome

Applicants can take a number of actions that can mitigate against these less desirable consequences and still obtain the benefits of an EPO international search.  These include:

Filing an EPO-style claim set when filing the PCT application, with multiple dependencies and alternatives in claims; and limiting the number of independent claims.  Where multiple independent claims are necessary to define the invention, these need to be arranged such that the first independent claim provides a basis for the most relevant and broadest search.  This will tend to reduce the likelihood or impact of lack of unity issues,ensuring that the search covers all possible combinations of subject matter that may be required during prosecution to amend claim scope for allowability. 

Pay multiple search fees where lack of unity is alleged.  Even if it is not possible to include all claimed inventions in one national or regional phase application, any divisional applications can be based on an informed decision regarding patentability.  In the EPO, the search fee for the divisional application may be reduced or exempted based on the further PCT search.

Ensure that claims to methods of treatment, business methods, and the like appear after normal composition, apparatus, system or method of manufacture claims.  This strategy improves the chances that the search and opinion will focus on the core of the invention rather than being widely drawn and providing little guidance. 

In addition, it can be useful to use the possibility of international preliminary examination (IPE) under PCT Chapter II to address some of these issues, even if a positive outcome may be unlikely.  Even though the EPO may decline to examine second or subsequent inventions during the regional phase, when acting as IPEA, the EPO will examine all inventions for which international search fees and examination fees have been paid.  This can provide an applicant with better information for deciding which invention should be pursued in the EPO and other patent offices, and whether or not to file a divisional application.  A positive outcome during IPE will lead to the EPO phase application proceeding directly to grant.  It is also useful to remember that filing the demand for IPE does not oblige the applicant to proceed at the national phase with the claims on file at the end of IPE, they can still proceed with original claims.  This can be particularly useful if there are two possible lines of amendment or argument to address matters raised in the search.  Amending or arguing one of these during IPE then leaves the possibility of redirecting prosecution on entry the EPO regional phase to another without the risk of refusal of the examiner to exercise discretion and allow the new line to be presented. 

In all of these cases, it is useful to note that the PCT application as-filed is considered to be the EPO application and any amendments during the EPO phase will be judged against the original PCT application.  Thus, it is advisable to review the application before PCT filing to ensure that its content provides suitable support for likely amendments under EPO rules, as post-filing amendment possibilities are more limited.  Also, as IPE before the EPO is essentially similar to normal prosecution at the EPO, the use of a European patent attorney can be useful to avoid common issues due to differences in US and EPO procedure. 

With appropriate preparation and conduct, the EPO can provide a great benefit for US applicants seeking international patent protection via the PCT, without bringing unintended consequences due to differences in procedure.

This article previously appeared in Full Disclosure Patent Newsletter, September 2014.

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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