Depending on the type of intellectual property you own, some rights will not be affected. Whereas for EU ‘unitary’ rights which are only enforceable in EU member states, once out of the EU, such rights will no longer apply to Britain.
IP registrations are territorial rights, which means they are only enforceable in the territories where they are registered. Therefore, unless your IP rights are registered in the EU, they will not be protected or enforceable in the EU.
If your trade mark or design is registered in the UK, the registration will not be affected by Brexit. If, however, your registration is in the EU (which is a ‘unitary’ and territorial right), post-Brexit such registration will not cover the UK, but will continue to have effect in the other remaining EU member states.
Your rights to trade in the EU are not dependent on your IP registrations. However, after Britain leaves the EU, you will not be able to take legal action against any infringement in the UK on the basis of your EU registration, even if you are a UK-based business.
If your trade mark or design is registered in the EU, then you will continue to be able to take legal action against infringements or unauthorised use of your trade mark or design in the EU. But if you only have a UK registration for your trade mark or design, then you do not have any right to stop infringements or unauthorised use in the EU.
It depends on whether they have registered their trade mark or design in the UK. EU-based companies that only own EU registrations will not be protected in the UK.
If you own EU registrations for your trade mark or design, it is advisable to also now apply for a separate registration in the UK to avoid any gaps in your IP protection. If you already own UK registrations but intend to start, or continue, trading in the EU, it would be advisable to separately file for registration in the EU.