Patent filing process - eight things you need to know

Clare Collins

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Reviewed on 10th May 2024

Patent filing can seem complex. If you’re thinking of filing a patent, but aren’t sure where to start, you’re in the right place. Here, we cut through the jargon to identify eight key things you need to know about the pre-filing, filing and post-filing patent process.

What you need to know... before filing a patent#

1. Confidentiality#

First things first, you must keep your invention secret before filing a patent application. It can be very difficult to obtain protection for any disclosed aspects of your invention. Where necessary, use non-disclosure agreements (NDAs) if you are talking to third parties such as investors or developers.

Once you have filed a patent application you are free to disclose any aspects of the invention that have been described in your patent application without prejudicing the patentability of your own invention.

2. Patentability (assessing the novelty and inventive step)#

To be patentable, an invention must be new (novel). Anything that has been made publicly available before the filing date of your patent application can be cited against it. In the UK and Europe this includes disclosures made by yourself concerning your own invention, which is why pre-filing secrecy is important.

As well as being new, it must also be inventive (non-obvious). This means that the new features of the invention can’t be obvious to a person working in that technical area if they try to solve the same problem. In practice, this means showing that your invention provides a technical solution to a technical problem.

3. Pre-filing searches#

You can get an initial idea about whether an invention is already known by carrying out keyword searches using free online tools such as Espacenet, Google Patents or the US Patent and Trademark Office website.

While keyword searches aren’t comprehensive, they can give you a rough idea about what is already out there and may help to determine which aspects of your invention you are particularly keen to focus on protecting. Although not mandatory, you may then also wish to instruct professional, in-depth IP searches.

What you need to know... when filing a patent#

4. Drafting#

Once you have decided to file a patent application for your invention, you need to prepare the application itself. A patent application includes a detailed description and technical drawings, along with a set of claims that define the scope of protection. It must explain how the invention works in some detail, with particular focus on the new features and functions that aren’t already known. In other words, the description needs to provide a skilled person with an enabling discourse of the invention.

5. Priority date#

The date on which you file the application at a patent office for the first time is known as the priority date. This is also the date at which the novelty and inventive step are assessed.

6. Subsequent filings#

Patents are jurisdictional. To protect your invention, protection must be pursued separately in each jurisdiction. You have 12 months from the priority date in which to file further patent applications in other jurisdictions. This is called the priority period.

One way to proceed is to file direct applications in each of the jurisdictions you’re interested in - on or before the expiry of the priority period. By claiming priority to your first application, you can keep the priority date. This can be important for reasons relating to novelty and inventive step, particularly if you have subsequently disclosed your invention after the priority date.

In Europe, it’s possible to file a patent application at the European Patent Office (EPO) from which you can centrally prosecute an application. Granted ‘EP’ patents can be validated in a number of countries post-grant. Note that the EPO isn’t related to the EU. Patents granted by the EPO can be validated in the UK.

Another way to proceed is to file a so-called International application via the Patent Corporation Treaty (called a PCT application), again claiming priority to your first application to maintain the priority date. A PCT application doesn’t result in any ‘international patent’ — you will still need to file applications for patents based on the PCT application separately, in every jurisdiction. Filing a PCT application can be an attractive option because it buys you a further 18 months (giving you 30 months in total from your priority date) to decide on where you would like to file future patent applications. Note that a patent term always starts from the filing date, not the priority date.

The patent application (and any subsequently filed patent applications) are published 18 months after the priority date.

Note that the term (duration) of a granted patent is always 20 years from the filing date of the application (which may be different to the priority date).

What you need to know... after filing a patent#

7. Search and examination#

In each jurisdiction that a patent application is filed, the patent office will conduct a search (although some patent offices don’t issue a separate search report).  This is to identify the documents used to determine the novelty and inventive step. These documents then usually form the basis of the examination procedure. While some effort has been made to standardise this process, each jurisdiction is individually responsible for patent prosecution, so different prior art may be cited worldwide. This means that it isn’t always possible to achieve the same scope of protection in every jurisdiction.

Once a patent office finds that the patent application meets the relevant criteria, it can be granted and enforced.

8. Fees#

There are various fees payable throughout the lifetime of a patent — a mixture of official fees (determined by patent offices) and professional fees (determined by attorney firms).

The fees include, but are not limited to:

  • Drafting fees — this will be based primarily on attorney time.  These fees will vary depending on the complexity of your invention.
  • Filing fees — some jurisdictions and patent applications are more expensive than others.  Expect to pay an official filing fee for filing a patent application.
  • Search and examination fees — this will include a mixture of official fees and attorney time.  While a patent office prepares search and examination reports, patent attorneys prepare and file responses to objections raised by the patent examiners. A typical patent may go through a few rounds of prosecution before it’s deemed acceptable.
  • Grant fees — this can include official fees such as publication and validation fees (for example when an EP patent grants) as well as translation fees (where appropriate).
  • Renewal fees — these are paid to patent offices, typically annually, to maintain the status of the patent.

If you’re thinking about filing a patent and need guidance, get in touch with us.

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