If we leave, it would have no effect at all on UK national registered rights. If Brexit ( btw Brexit is an abbreviation of “British exit” that mirrors the term Grexit….for Greece) happens then I have no idea how this would affect IP rights in the EU!
I would argue that it ought not make much difference for example Switzerland is not an EU member but it is a party to the EPC so why not grant the UK similar status and allow it to continue as a ‘member’ of sorts of some treaty.
Â The UK govermemt’s argument is hereÂ https://www.eureferendum.gov.uk/why-the-government-believes-we-should-remain/
Brexit hereÂ http://getbritainout.org/