If 4chan continues to ignore Ofcom, the forum could be blocked in the UK. And 4chan could face even bigger fines totaling about $23 million or 10 percent of 4chan’s worldwide turnover, whichever is higher. 4chan also faces potential arrest and/or “imprisonment for a term of up to two years,” the lawsuit said.
What? No it doesn’t, not as long as the people responsible don’t step foot in the UK.
If they do - yes they’ll be arrested for having broken UK law.