This all came up in the 1990s in the English High Court over whether Welsh clubs could play in Wales whilst being part of the English pyramid system. The Welsh FA had stopped them when it wanted to set up its own league (to protect its international status), and a group of the 'exiled' Welsh clubs (who had to play in English grounds like Hereford whilst banned from Wales) took them to court, led by Newport County - who's fans are still bitter as feck about it all The clubs won their case under Euroopean law, so could continue playing in the English system from Wales. So that set a legal precedent that it was anti-competitive to stop a club from one footballing jurisdiction plying its trade in another. Even with Brexit I would expect that case to be referenced in this latest legal tussle, which sounds vaguely similar. Will be very interesting to see how this one works out.
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