http://www.marca.com/2012/10/04/en/football/barcelona/1349339197.html
Two possible loopholes to keep club in Spanish league
Barça could stay in La Liga despite Catalan independence
If Catalonia were to gain independence from Spain it would mean that
FC Barcelona would have to leave the LFP (National Professional Football
League) with immediate effect. While the matter may be a distant
possibility that has not been studied by both the LFP and the RFEF
(Royal Spanish Football Federation), the regulations on the issue are
clear and concise. However, there may be a solution.
In order to be able to participate in official competitions in Spain,
football clubs must be affiliated to the Spanish Football Federation
through their corresponding territorial Federations.
There would be two regulation escape routes for Barça which would
allow the club to continue being affiliated by the Spanish Football
Federation and thus continue playing in La Liga. One of these options
would be to become affiliated in a territorial Federation in Catalonia.
This option comes under regulation as something exceptional that would
have to be approved by the Board of the RFEF. In other words, the club
would be able to participate in La Liga, affiliated to the Federations
of Aragon, Valencia or any other zone.
However, this is not the only alternative. The other option would be
to benefit from the exceptional situation that the Principality of
Andorra has, which allows participation in the Spanish league. The
Andorra side currently plays in the Segunda División B. This option
would therefore be feasible, as Catalonia, despite being an independent
country, depends on sport in relation to Spanish legislation and its
Federation.