FAQs und Guides

Patents - Client FAQs

Introduction to patents

Please read our Introduction to Patents guide for essential information about what a patent is.

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Our Patent FAQ are intended to answer some of the more common questions and to clarify some common misunderstandings about patents. This information is based on UK and European patent law (although much of this information is also relevant to other jurisdictions). Please note this section is for general informational purposes only and should not be taken as legal advice. For legal advice specific to your circumstances, please contact a D Young & Co attorney or solicitor.

What can I get a patent for?

You can get a patent for an “invention”. An invention is technology which provides a solution to a technical problem. A patent protects the technical way in which the invention works in order to solve the technical problem. It cannot be used to protect other aspects related to the invention, such as the way it looks aesthetically, a brand name for the invention or a business model for selling the invention. Some of these other aspects are protectable using other types of intellectual property rights, e.g. a registered design to protect the aesthetic look of a product or a trademark to protect the brand name. Information about other types of intellectual property rights can be found in our IP right guides.

What are the requirements of the invention?

The invention must be new, must involve an inventive step and must be industrially applicable.

In order to be new, the invention must not have been made available to the public (e.g. by publishing a paper explaining the invention or by selling or advertising the invention) prior to the effective filing date of the patent. The effective filing date is the date on which the patent application was filed at the patent office or, if the patent validly claims priority from an earlier patent application (see below), the date on which that earlier patent application was filed. In most major jurisdictions (including the UK and Europe), an invention owner’s own disclosure of their invention to the public prior to them filing a patent application prevents them from obtaining a patent for their invention. It is therefore important to keep your invention secret (or to only disclose the invention to certain parties confidentially) until a patent application has been filed.

In order to involve an inventive step, the invention must be non-obvious based on what is already known. It is therefore not possible to obtain a patent by simply taking an existing invention and modifying it in an obvious way so as to arrive at something new. Rather, there needs to be an additional inventive aspect to the invention which goes beyond a mere obvious modification of what is already known. The question of inventiveness is usually more subjective than that of whether or not the invention is new. Often, an invention can seem obvious in hindsight (i.e. once you already know what the invention is). However, there may be good arguments that, based purely on what was known prior to the invention (i.e. without hindsight), the invention is certainly not obvious. Part of the job of a patent attorney is to be able to spot such arguments and to convey these when arguing to the patent office that a patent should be granted.

In order to be industrially applicable, the invention must have a practical industrial application (e.g. it can’t be purely of academic interest). In practice, nearly all inventions could (at least in principle) be applied in some sort of industrial context. This requirement is therefore typically a low bar to patentability.

What does “claiming priority” mean?

“Claiming priority” means that the date at which it is judged whether or not the invention is new and involves an inventive step (i.e. the effective filing date) is backdated to the filing date of an earlier patent application. The filing date of the earlier patent application from which a later patent application claims priority is known as the “priority date” of the later patent application.

The main purpose of claiming priority is to allow patent applications having the same applicant and relating to the same invention to have the same effective filing date in all countries in which those patent applications are filed. It is possible for a later patent application to claim priority from an earlier patent application as long as that later patent application is filed within 12 months of the earlier patent application and the earlier patent application is the first patent application filed by the applicant which covers the invention in question. Worldwide patent protection can thus potentially be obtained by starting with a single patent application filed in a single country. It is important to note that there is no such thing as an international patent. A separate patent is therefore required in each jurisdiction in which you wish to protect your invention.

What form does a patent take?

A patent is essentially a legal document explaining what the invention is and the extent to which the invention is protected. In particular, the patent will contain a written description of the invention (and, optionally, one or more drawings to help explain the invention) and a set of one or more claims.

The description and (if present) drawings explain how the invention works. The description must contain sufficient detail such that a skilled person (e.g. engineer working in the technical field concerned) could make the invention based on the teachings of the description.

The claims define the legal scope of protection provided by the patent.

What’s the difference between the claims and the description?

To illustrate the difference between the claims and description, let’s consider a simple example in which the invention is a bicycle (let’s ignore the fact that, in a reality, bicycles are already known to the public and are thus not patentable!).

The description will provide a comprehensive explanation of what a bicycle does and how it works by way of specific examples (or “embodiments”) of a bicycle. It might reference a schematic drawing of an example bicycle (which will be one of the drawings of the patent) in which the various bicycle components (e.g. the frame, wheels, handlebars, saddle, peddles, chain, gears, bell and brakes) are labelled and give an explanation of what each component does and how it interacts with the other components in order to allow the bicycle to function. All information which an appropriate “skilled person” (e.g. an engineer or mechanic) would need in order to build a bicycle should be given in the description.

The claims, on the other hand, define exactly what the patent protects. Each claim is a long sentence defining the essential features that make the invention what it is. The claims should be as broad in scope as possible so as to cover all envisaged ways of implementing a bicycle but narrow enough in scope such that what they define is new and inventive. In other words, the claims should define the minimum number of features which are required for the invention to work and for the invention to be new and inventive, and nothing else. The claims are thus usually broader in scope than the specific example(s) of the invention given in the description. Writing suitable claims which both (a) cover all envisaged embodiments of your invention and (b) are acceptable to the patent office in terms of being new and inventive is often tricky. It is, however, something that patent attorneys are specifically trained to do.

An example set of claims for a bicycle is given below. Note that the claims contain a lot less information than the above-mentioned description!

Claim 1: A vehicle comprising a frame and two wheels attached to the frame.

Claim 2: A vehicle according to claim 1, further comprising rotatable pedals attached to one of the two wheels via gears and a chain.

Claim 3: A vehicle according to claim 1 or 2, further comprising a seat.

Claim 4: A vehicle according to any preceding claim, further comprising a bell.

Claim 1 is known as an independent claim because it does not refer to any other claim (i.e. it stands independently). The scope of protection afforded by a patent is the scope of its one or more independent claims.

Claims 2 to 4 are known as dependent claims because they each depend on (i.e. have the features of) at least one other claim. The scope of protection afforded by the patent is not limited by the content of the dependent claims in the same way as it is by the content of the independent claims. Rather, the dependent claims are there as so-called “fall-back” positions for use in case the independent claim on which they ultimately depend (and which defines the scope of protection of the patent) is found not to be valid (e.g. not new or not inventive). An independent claim may be found not to be valid before grant of the patent (e.g. during examination of the patent application) or after grant (e.g. if invalidity proceedings are brought in court against the patent). In this case, the owner of the patent (or patent application) may be given the opportunity to narrow the scope of the independent claim in order to try to make it valid and may do this by inserting the subject-matter of a valid dependent claim into the independent claim.

Does a patent always have both claims and a description?

Yes. The arrangement of having a description and separate claims was developed to achieve the two primary functions of a patent, these being (1) to provide a (temporary) monopoly over the invention to the owner of the invention (thereby providing an incentive for inventors to invent) and (2) to share with the world how the invention works (thereby allowing others to use or sell the invention once the patent has expired and providing the technical information necessary for potential further innovation in the field).

The claims are intended to achieve function (1) whereas the description is intended to achieve function (2). It would be difficult for the claims or description alone to achieve both functions. The minimal wording of the claims, although good for defining the scope of protection, might not provide enough information for a skilled person to actually be able to implement the invention.

On the other hand, the detailed examples of the description, although good for demonstrating how the invention works, might not form a good basis for the scope of protection. For example, if someone started selling bicycles which looked different or had some different non-essential components to the example bicycles of the description, would this activity still be covered by the patent? A patent therefore has both a description and one or more claims in order to satisfactorily achieve both its intended functions.

What does a patent allow me to do?

A granted patent gives you the legal right to prevent a third party from working the invention covered by the patent. For example, you can stop a third party from using, making or selling the invention. If a third party does any of these activities without your permission, they are said to be infringing the patent. Legal remedies (e.g. an injunction or damages) may then by sought against the third party. A granted patent does not, however, necessarily give you the right to use the invention. This is because another, earlier patent might already cover the invention.

To demonstrate this, let us again consider the bicycle example mentioned above. It is possible (again, ignoring the fact that, in reality, neither claim 1 nor claim 2 are new!) that a first party has a patent for the subject-matter of claim 1 (i.e. a bicycle with a frame and two wheels) but that a second party has a patent for the subject-matter of claim 2 (i.e. a bicycle with a frame and two wheels, but also with pedals, gears and a chain). In this case, we are assuming that the independent claims of separate patents owned by the first and second parties consist of the features of claims 1 and 2, respectively. Such a situation is quite common for improvements to existing inventions covered by a patent (in this situation, the bicycle with pedals, gears and a chain can be considered an improvement over a bicycle with just a frame and two wheels). If the second party sells a bicycle having all the features of claim 2 (frame, two wheels, pedals, gears and a chain), then that bicycle necessarily also has all the features of claim 1 (frame and two wheels), thereby infringing the patent of the first party. The second party’s patent thus does not entitle the second party to exploit the invention covered by that patent. It can, however, stop the first party from exploiting this invention (i.e. it can stop the first party from selling bicycles with pedals, gears and a chain in addition to a frame and two wheels).

Depending on the commercial interests of the two parties, this sort of situation can sometimes be resolved by way of a so-called "cross-licence", in which, for example, the first party allows the second party to sell bicycles with a frame and two wheels (as covered by the first party's patent) as well as with the additional pedals, gears and chain in return for the second party allowing the first party to also sell such bicycles (without this allowance, the first party could be stopped from including the "improving" features of pedals, gears and a chain, as covered by the second party's patent, in the bicycles it sells). The details of such licences (if granted at all) can vary wildly depending on the commercial interests of the parties involved.

Is a patent worth it?

Well, it depends. It's important to note that a patent itself has no intrinsic value. There is no prize money or other award (other than a patent grant certificate) given out by the government once a patent has been granted. In fact, the act of obtaining and maintaining a patent only costs you money. Rather, the value of a patent depends on the commercial value of the invention covered by the patent. A patent which covers an invention for which there is no demand is unlikely to be of much value (there is very limited value in being able to stop someone from making, selling, etc. an invention which no one wants anyway). On the other hand, a patent which covers an invention for which there is high demand may be very valuable (since the patent holder controls who is able to make, sell, etc. the invention). Of course, given that a patent application for an invention must be filed before that invention is sold (or publicly disclosed in any other way), it is often not possible to know the commercial demand for an invention prior to filing a patent application for it. The costs associated with filing a patent application and following it through to grant should therefore be considered as an investment, which may or may not pay off (depending on the future commercial demand for the invention in question and how well it is monetised).

As with any investment, it is thus a good idea to have some knowledge of the pros and cons associated with patents.


  • A patent which covers the technology behind how your invention works is the only way to protect that technology once it is out for all to see in the marketplace. If a competitor is able to legitimately work out how your invention works (e.g. by buying it from a shop and taking it apart) and recreate this technology in one of their own products, then there is very little you can do to stop them without a patent.
  • Having a patent (or at least a patent application) covering an invention before you demonstrate that invention to third parties such as investors makes the ownership of the technology clear to everyone involved. This is because a patent application filed at the patent office essentially acts as an official record of what the invention is (as defined by the claims) and who owns the invention (as defined by the applicant of the patent application) and gives a date (in the form of the filing date or, if applicable, the priority date) at which that ownership is formally established. This helps give peace of mind to both you (since you know that, if the patent is granted, the invention cannot be used by the third party without your permission) and to the third party (since they know exactly what technology is owned by you and what is not). It is quite common for investors not to sign any non-disclosure agreements and to make it clear that you are responsible for protecting your own intellectual property prior to sharing any information with them about an invention. This makes patent protection important if you intend on doing business with such investors.
  • Having a patent may allow you to monetise an invention which, due to the large amount of resources typically needed to produce and bring an invention to market, you might not be able to do without help. For example, you can sell or licence a patent for a desirable technology to a third party with more resources than you (and who are therefore able to produce and market the invention more easily) in return for a one off fee (in the case of selling the patent) or a share of the profits (in the case of licensing the patent).
  • Having a patent covering an invention may make the invention more attractive as an investment opportunity to third parties (since they will know that the patent allows them to stop competitors from copying the invention, thereby potentially making it more profitable).
  • If you are operating in a market in which a competitor has patents, then you are generally in a much better negotiating position if, for example, you are accused of patent infringement. For instance, you may be able to counterclaim for infringement if one of your accuser’s products infringes one of your patents. In many cases, this can lead to negotiation of a commercial solution between you and your competitor (such as a cross licence between you and your competitor for the patents in question), thereby avoiding a costly legal battle (which you may or may not win). If you don’t have any patents, then this option is not available to you.
  • It may be possible to reduce the amount of corporation tax paid in certain jurisdictions for profits earned from patented inventions. The UK’s Patent Box is one such scheme.


  • Like any business investment, pursuing patent protection involves various costs. In particular, preparing and filing a patent application, negotiating with the patent office to try to get it granted and keeping the patent in force requires various official fees and, if using a patent attorney, attorney fees to be paid. The exact cost is variable according to a number of factors (such as the jurisdiction in which the patent is sought, the technology area and the complexity of the invention). However, as a very rough estimate, expect to spend around £10,000 to £20,000 per patent over the lifetime of the patent (the lifetime being 20 years from filing of the patent application in most jurisdictions), with a significant proportion of these costs being due in the first few years after filing the patent application. It is also important to remember that a separate patent is generally required for each jurisdiction of interest, and thus this approximate £10,000 to £20,000 cost should be multiplied by the number of jurisdictions in which you wish to obtain patent protection.
  • Apart from a small number of exceptions (e.g. some military inventions), the content of all patent applications is eventually made public (usually around 18 months after filing the patent application). This means that anyone may then read the patent application and find out how the invention works (recall that a patent application must include all information that an appropriate “skilled person” would need in order to reproduce in the invention). This allows the invention to be used freely after the patent has expired and gives others the knowledge required to potentially improve the invention (and perhaps file their own patent applications for such improvements at a later date). In some cases, it might therefore be more appropriate to protect a particular invention by simply keeping how it works a “trade secret” (and not filing any patent applications). This can be risky, however, especially if it is possible for a competitor to reverse engineer your invention and find out how it works. For this reason, keeping something a “trade secret” is only really a sensible option if reverse engineering the invention (or finding out how it works in some other legitimate way) is known to be very difficult.

I’ve filed an application! Do I have a patent now?

Unfortunately not. As might have become apparent from some of the previous answers, you must first file a patent application. This patent application (after payment of the appropriate patent office fees) is then reviewed by the patent office in order to determine whether the patent application complies with the patent law of the relevant jurisdiction.

In most major jurisdictions (including the UK and Europe), this review involves the patent office conducting a “prior art” search based on the claims of the patent application to find out if what is claimed is already known or is obvious from what is already known. “Prior art” is everything that is publicly known prior to the filing date (or, if applicable, the priority date) of the patent application. Prior art includes a wide range of disclosures such as academic papers, previous patent applications, products on sale and even oral descriptions (e.g. as might occur in online videos or at academic conferences). For practical purposes, the prior art usually cited by patent offices tends to be in written form (e.g. previously published patent applications or academic papers), although it is not limited to this. The review then includes examining the patent application in light of the prior art which has been found in order to determine whether the invention defined in the patent application is new and inventive. The examination also includes, for example, checking that the patent application complies with all the formal requirements of the patent office.

If the patent office finds any problem with the patent application, then it raises a formal objection and you are given the opportunity to provide arguments and/or amendments to try to overcome this objection. The most common objection is that the invention defined by the independent claim(s) of the patent application is, in the opinion of the patent office, not new (this is known as a novelty objection) or does not involve an inventive step (this is known as an inventive step or obviousness objection) in view of prior art found during the search. In this case, it is necessary to review the prior art, study the patent office’s reasons for alleging that the invention is not new or inventive and determine whether or not you agree with the patent office’s conclusion. If you do not agree, then arguments can be made to the patent office in order to try to get them to change their mind. If you do agree, then it is possible to make amendments to the patent application. This may involve, for example, inserting a new feature into the independent claim(s) of the patent application (which, you will recall, defines the scope of protection of the patent) so as to arrive at a combination of features in the independent claim(s) which is not known or obvious from the prior art.

Importantly, it is only possible to include new features in the independent claim(s) which were included in the patent application when the patent application was originally filed. To use the example claims above, it would therefore be possible to amend claim 1 to include the subject-matter of any one of claims 2, 3 or 4 (assuming they were included in the patent application when it was originally filed) or to include some wording from the description which was included in the patent application as originally filed. It would not, however, be allowable to amend claim 1 to insert a completely new feature which was not included in the patent application when it was originally filed. The rationale behind this is to prevent applicants from being able to add whatever features they like to the claims of their patent application (and to thus potentially obtain patent protection for those features) when those features were not disclosed in the patent application in the first place. It is therefore important that all features of an invention which might be valuable to have in a claim are included in the patent application when it is first filed, since it is not generally allowable to add new information to the patent application at a later date.

It is common for there to be several rounds of correspondence between an applicant and the patent office (the patent office raising objections and the applicant responding with amendments and/or arguments) before a patent is granted. It can be useful to think of this process as a negotiation. It is beneficial to the applicant to have the broadest scope of protection that the patent office will allow. However, the patent office cannot grant a patent for an invention which it considers to be already known or obvious from what is already known. The negotiation between applicant and patent office (known as patent “prosecution”) thus ideally results in finding some middle ground which is both commercially valuable to the applicant and acceptable to the patent office. Only once the patent office has been presented with an independent claim(s) which it finds acceptable will it grant a patent application (at which point, the patent application becomes a patent). The length of time taken to grant a patent can vary significantly for different jurisdictions, but is typically of the order of several years.

Can I do anything whilst waiting for my patent application to grant?

You cannot enforce a patent until it is granted. However, once a patent application has been filed, you can freely disclose your invention (as disclosed in the patent application) to the public (e.g. by selling it or by presenting it to investors). Also, once the patent application has been published, this gives you a form of provisional protection which (with some limitations) allows you to back date an infringement claim to the date of publication. You are also allowed to inform people that you have a patent application pending for your invention.

If the patent office cites other published patent applications as “prior art” in their search, does this mean I might be infringing these patents?

Not necessarily. It is important to remember that not all patent applications which get published (and which are therefore citable as prior art) get granted (e.g. some are refused by the patent office and others are abandoned or withdrawn by their applicant) and that even those which are granted need to have a granted set of claims which covers what you do in order for you to be an infringer. It is quite common for published patent applications cited as prior art by patent offices to never actually proceed to grant or to grant with a claim scope which doesn’t cover what you do.

That said, if you are concerned that you might infringe another party’s patent(s), then talk to a patent attorney, who will be able to provide you with appropriate advice. If there is a particular patent or patent application that you are concerned about (you cannot infringe a patent application, but you may be concerned that you will infringe it if and when it grants), then a patent attorney will be able to review the patent or patent application in question in light of the activity you intend to do (e.g. sell a product or carry out a particular technical process) and provide an opinion as to whether or not you infringe. If you are concerned about other party’s rights in general, then it is possible to get a so-called “freedom-to-operate” search carried out in order to identify potentially problematic patent rights which can then be reviewed by a patent attorney.

In general, how to manage the risks associated with other people’s patents is a commercial decision which depends on several factors, including the nature of your business, the aggressiveness of your competitors and your aptitude for risk. At one end of the scale, some businesses take a more “active” approach of conducting thorough freedom-to-operate searches and analyses in all relevant jurisdictions prior to launching any new product. The downside of this is the associated cost in search fees and attorney hours. At the other end of the scale, some businesses take a more “passive” approach in which freedom-to-operate searches and analyses are not routinely carried out and potential infringement of third party rights is only considered when necessary (e.g. if accused of patent infringement). This saves the cost of search fees and attorney hours, but is arguably more risky. There are several “middle of the road” options (e.g. not conducting full freedom-to-operate searches for every new product launch but, instead, keeping a watch on your competitors’ patents and patent applications to identify potential risks). Again, talking to a patent attorney about your specific situation is usually helpful in coming to a decision about which approach might be most appropriate to your business.

What if I want to enforce my patent against a competitor?

Talk to a patent attorney. They will be able to review the claims of your patent against the activities of your competitor and provide you with an opinion as to whether or not you have a case for patent infringement. They can then advise you on next steps. If it is determined that the competitor is likely to be infringing, then the next steps could involve, for example, engaging in legal action against the competitor in court, offering them a licence (e.g. in return for royalties) or coming to some sort of other “out-of-court” agreement.

Again, the most appropriate way forward is usually a commercial decision which depends on several factors, such as the nature of your business (e.g. how important the monopoly conferred by your patent is to your commercial success), the aggressiveness of your competitor (e.g. how likely they are to back down or fight back) and your aptitude for risk (e.g. court proceedings are very expensive and there is no guarantee that a judge will decide in your favour). These factors can all be discussed with your patent attorney.

Note that, when thinking of enforcing a patent against a competitor, it is important to involve a patent attorney or other suitably qualified legal professional before taking any action, since groundlessly threatening someone with patent infringement can result in legal action being brought against you.

I’ve been accused of patent infringement by a competitor. What do I do?

Talk to a patent attorney. They will be able to review the claims of the patent in question against your allegedly infringing activities and provide you with an opinion as to whether or not your competitor has a case for patent infringement. They can then advise you on next steps. The next steps could involve, for example, engaging in legal action against your competitor in court (e.g. by fighting the infringement claim and/or bringing invalidity proceedings to try to prove that the patent should never have been granted and is therefore not enforceable), offering to take a licence from your competitor (e.g. in return for paying them royalties) or coming to some sort of other “out-of-court” agreement.

Again, the most appropriate way forward is usually a commercial decision which depends on several factors, such as the nature of your business (e.g. how important your allegedly infringing activities are to your commercial success), the aggressiveness of your competitor (e.g. how receptive they are likely to be to a commercial negotiation instead of pursuing court proceedings), your negotiating position (e.g. you could make your competitor aware of any of your own patents that they arguably infringe, which might make them more receptive to avoiding court proceedings and working with you on a commercial solution) and your aptitude for risk (e.g. court proceedings are very expensive and there is no guarantee that a judge will decide in your favour). These factors can all be discussed with your patent attorney.