UK patented product produced in China

To add a little to what Jon said, a patent issued in any country can generally be used to stop others from making, using, selling, offering for sale or importing the patented invention in that country. If none of those activities are occurring in a country where you have a patent, you probably have no recourse.

This is a very complex scenario, and it's not possible to answer this question adequately without some more information. What kind of product is it? Where (in what countries) is your patent protection? What kind of patent do you hold -- is it a utility patent or a design patent? Is the unlicensed product being sold only in South Korea? Or is it also being sold in the UK and elsewhere? In what countries are you selling your product?

You have asked if there is any way to protect your IP in the UK -- but perhaps you are actually asking whether there is any way to defend your existing patented product in the UK. If there is a copycat coming into the UK where you are operating, and if you have relevant patent protection in the UK, then you definitely should consult with a UK solicitor about the options available to you, which may include a patent infringement suit.

With regard to the product being sold in South Korea by your competitor, if you do not have patent coverage in South Korea, it will be difficult, if not impossible, to mount an effective legal challenge there or anywhere else.

It sounds like a good first step would be to confer with a UK solicitor. He/she can advise you whether there are any worthwhile countermeasures that can be taken. And you might want to explore the feasibility of extending your patent protection to countries where your competitors are selling knockoffs.

We are happy to connect you with great UK lawyers, There are also several in this Directory.

There's this neat trick of putting out a software driver that disabled clones of a USB hub chip but I suspect self-help mechanisms are not well recieved. Unless you change subcontractors, perhaps a legal approach formalising the reality and asking for cross-licensing fees may be a compromise.