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How do I know whether tickets I buy in the street or other places are valid?
FCB only advises you to purchase tickets from the official channels, the FCB website, the FCB ticket offices, or the Ticketmaster website).
There are other sales channels that are identified as official FCB outlets (FCB stores, Barcelona Tourist Office, agencies).
FCB will only be held responsible for tickets sold directly via its own sales channels (FCB website and FCB ticket offices). For incidents involving tickets purchased from other channels, you will have to communicate directly with the channel / supplier from which you purchased the tickets.