The Patentability of Computer Software in Europe

November 1, 2000

Thecurrent UK and European patent laws have a common origin and date from thelate1970s but have their origins in the 1960s. In the 1960s computers were rareand expensive. While matters were changing, a significant proportion of computersoftware was then still written on a bespoke basis. Few could conceive the majoradvances in computer power, affordability and application which would shortlyfollow. The general perception was that the majority of advancements in computerprograms would be best protected using copyright. Accordingly the new law inEurope and the UK included a number of statutory bars which affect thepatentability of computer software related inventions (SRI). Many people believethat the patenting of computer software of any kind is not possible in the UK orEurope. This is not correct. The President of the European Patent Office (EPO)recently estimated1 that fewer than 200 applications for SRI had beenrefused on the ground that they were computer programs and that more 20,000 hadbeen granted.

The UK Patent Office is obliged2 to adopt the same standard ofpatentability as the EPO. The received wisdom is that they do not and apply astricter standard. My experience is that the standard is rather similar but thatin borderline cases one office may accept something to which the other objects.By way of anecdotal example, the UK Patent Office granted clients of mine GB 2303 475 for a neural network system for detecting mineral deposits (commerciallyembodied in Neural Mining Solutions’ Prospect Explorer) to which the EPOobjected. Conversely the EPO granted other clients of mine EP 592 421 for acomputer software based method of drug design (commercially embodied in TriposAssociates’ CoMFA) to which the UK office objected. The simple answer inimportant and borderline cases is to hedge bets and file applications beforeboth the EPO and the more important national offices.

The precise wording of the statutes differs in minor respects. The EPOversion3 reads as follows:

  1. [P]atents shall be granted for any inventions which are susceptible of industrial application, which are new and which involve an inventive step.
  2. The following in particular shall not be regarded as inventions within the meaning of paragraph 1:

    1. … . . mathematical methods;
    2. … .;
    3. schemes, rules and methods for performing mental acts, playing games or doing business, and programs for computers;
    4. presentations of information.

  3. The provisions of paragraph 2 shall exclude patentability of the subject-matter or activities referred to in that provision only to the extent to which a European patent application or European patent relates to such subject-matter or activities as such.

It can be seen that there a number of potential grounds for rejection ofclaims for SRI.

Does the mere presence of a computer program in the claimed invention renderthe whole unpatentable? For example, suppose that the invention is a novel andinventive method of machining metal. Some of the steps require carefulpositional and timing control and the only convenient way of doing this is bysoftware. It is now well established4 law that this does not destroythe patentability of the system. In ‘EPO-speak’ there is still a newtechnical effect because the result is a better method of machining.

Consider now a computer with two banks of memory. The first is fast butexpensive and the second slow but cheap. The invention consists of a computersoftware which controls the computer in such a way that the computer processesinformation about as quickly as if all the memory was fast. This could beregarded as a combination of a known and therefore unpatentable computer with acomputer program unpatentable ‘as such’. However there is still a newtechnical effect – the combination is a computer which processes informationfaster than it otherwise would. The invention therefore is patentable, althoughuntil recently (see below) a good deal of care would have been necessary indefining the invention.

Suppose now one devises a method of determining the lowest energyconformation of some bodies bearing an electrical charge. This is a discoveryand excluded from patentability. The algorithm by which it is done is amathematical method and also excluded from patentability. A computer program todo the ‘number crunching’ is a computer program ‘as such’ and excludedfrom patentability. If part of the program displays the result in such a waythat the user gains an insight into the steric interaction between the chargedbodies then again this will be statute barred as either a computer program orthe presentation of information. But use the charged bodies as representationsof the interaction of drug candidate molecules and receptor sites (those partsof the body to which the drug binds giving rise to the therapeutic effect) andyou have a method of processing data representing a technical structure orprocess which at least in the view of the EPO is patentable. Hence it waspossible to patent the CoMFA program.

Once the existence of a patentable invention is recognised some thought hasto be given to its definition in the claims. Outside the USA,5 mypreference where possible is to claim the invention in terms of apparatus ormethod for a particular function comprising means for performing each of theessential steps. This has the advantage that it is not limited to implementationin a conventional computer (who knows what will be used for computing in 20years?). Claims to a computer programmed in an inventive way are acceptable andcommonly seen. Claims to a program carried on computer readable media have longbeen objected to as the combination of a known and hence unpatentable mediumwith a computer program unpatentable ‘as such’. Two recent decisions by theEPO’s Technical Board of Appeal6 recognise the inconsistencybetween this approach and the patentability of a known computer running acomputer program referred to above. The EPO and UK offices will now acceptclaims in this form. They have gone still further and now accept that a computerprogram capable of producing a technical effect when running is not merely acomputer program and thus is patentable. The new acceptance of claims tocomputer programs per se and machine readable carriers bearing them isimportant. Manufacture, sale, or importation of a computer program or a mediacarrying one is at least arguably not primary infringement of a claim to acomputer running a program but it is primary infringement of a claim to theprogram per se or media carrying it. Since in most cases it would be difficulton practical or PR grounds to institute proceedings against the users ofprograms, the newly acceptable claim structures are a very useful tool.


  1. Conference on Software Patents in Europe, 23 March 1998.
  2. Patents Act 1977, s 130.
  3. EPC, Article 52.
  4. Guidelines for Examination in the EPO C IV 2.3.
  5. For many years in the USA it had been believed that the expression ‘means for’ was very broad but a recent decision is that a very narrow interpretation should be applied.
  6. T0935/97 and T1173/97.

Tim Rickard of Shawn Coulson London (MoonBeever) is a chartered patentagent and european patent attorney. Contact him at