First off, apologies for the capitals in the headline, I just wanted to make sure I got my point across: Sergi Samper isn't leaving FC Barcelona, least of all for Liverpool FC, contrary to what some reports might suggest. Indeed, while some English media outlets have got excited about the rumours started by the notoriously inaccurate Fichajes, there's nothing to suggest that Samper himself is looking for a permanent switch away from the Camp Nou -- nor is there anything to imply that Barcelona would even entertain the idea of accepting a transfer bid.
Admittedly, that last point isn't particularly pertinent given the release clause in Sergi Samper's contract, a clause that currently stands at €12 million, but as is always the case with Spanish transfer rumours, the media outlets are only reporting half the story, typically due to ignorance on their part.
At face value, the €12 million sum seems like a bargain, especially for a player of Samper's talent and potential. However, the practical reality of these clauses in Spain is that they are ultimately payable by the player rather than the buying club. Now, there's nary a player on the planet with that kind of cash sitting around in their bank account and as such, the solution typically is that the buying club will transfer the money to the individual to make the payment to the authorities to release themselves from their contract with their existing club.
Of course, this clearly constitutes income for the individual and income is taxable by the authorities -- assuming that Samper is taxed as a resident in Catalunya, that means due to the scale of the figures involved, the payment from the purchasing club to Sergi is likely to be taxable at the highest possible rate -- 49%.
Once tax is therefore factored in, the actual price payable by the purchasing club could reach up to €23.5 million. Sure, Sergi Samper is a great talent, but let's be honest here: based on his minimal top flight experience, most clubs are probably going to balk at that pricetag. Ergo, Samper's staying folks and that's all there is to it.