March 2026 News

Can I re-register my patent?

We get asked this a fair bit, and the simple answer is “no”, although there are provisos to that (as ever…).  But why can’t you?  You can re-register a trade mark (again, provisos apply…), why can’t you do it for a patent?

The answer is quite simple.  A patent can be granted for an idea that is new, and not obvious.  It is new if the exact same idea can’t be found anywhere in any of the publications made by anyone, anywhere in the world, at any point in history, up to (but not including) the filing date.  That sounds hard to achieve, but in fact isn’t - the degree of coincidence required for it to be exactly the same as defined in your application is quite high, so there is often something we can use in the application to define a novel invention. 

Obvious is more subjective – to assess that, we take all the things that were disclosed before the filing date (known as the “art”), identify the closest one, and look at the difference(s) between it and the claimed invention.  If those changes are trivial, or just workshop variants, or just routine optimisation, or just the application of a suggestion made (publicly) somewhere else, then it’s obvious.  If there’s no suggestion in the art to head in that direction, and it’s not within the common general knowledge of a skilled person to make that change, then it’s non-obvious and potentially patentable.   

The other relevant factor is that patent applications (and the granted patents that result from them) are published – they were once physically printed off and put on the shelves of the Patent Office library, nowadays they are bundled into a pdf for easy download from one or more of a number of sites.  Publication typically happens at 18 months from your first filing date, so if you go back to the Patent Office at any point after that and file a fresh application for the same invention as was in your original filing, then the earlier publication of your own application forms part of the art that is citable against your later application.  And if you re-file the same application, then you will have achieved that remarkable coincidence of a prior publication that is exactly the same as your later application. 

So no – you can’t re-register a patent or a patent application once you’re that far into the process, because the idea is no longer new.  That’s one reason why it’s vital to stay on top of the procedural deadlines and response deadlines that arise during the application process and in relation to renewal fees – patent applications are typically a one-shot opportunity and if you get it wrong, there’s typically no second chance. 

The main proviso to the general rule is if you’ve made some kind of improvement or advance on the original version.  If that improvement is not an obvious development of the original, then you could file a patent application for the improved version.  A patent granted on that application would only be enforceable against someone who used the improved version; if you wanted to stop them using the original version then you need the original patent for that.  But if the original patent is gone, for whatever reason, it does mean that the third party has to stay behind the curve, they can only copy your (now-outdated?) original version.  You do need to file the new application before you disclose the new version though, such as prior to any sales of the new version. 

This is why it’s a great idea to build up a portfolio of patents, rather than just rely on the one patent that was applied for when the business started up.  That one patent may have been superb, groundbreaking, etc, but it has a filing date and in most technologies and most countries its expiry 20 years after that filing date is an absolute fixed point that cannot be got round.  20 years is one of those periods that feels like a long time when you’re at the start of it looking forward, but very short when you’re at the end looking back.  2006 feels like only yesterday for some of us… So if you keep the habit of adding new patent applications as and when you think of better versions of the product, then when you get to that 20-year expiry you may have to say goodbye to the central patent that founded the business, but there will be a raft of other patents around that central idea.  Your competitors can then copy the 20-year-old design, but can’t offer the up-to-date version.  And you can keep that strategy going for as long as you want. 

Let me know if you have any other questions, we’re always happy to talk through these issues.

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