Think this is the salient point:-
United land Jones for £16.5m (again) - Transfers, Football - The Independent
"United's refusal to offer more than their original figure for Jones is, in part, based on the outcome of the High Court case which followed Christian Ziege's move from Middlesbrough to Liverpool in August 2000.
Although Middlesbrough argued that Glasgow Rangers and Chelsea had both offered £7.5m for Ziege, Justice Astill said that the German had no market value as a player because Middlesbrough had agreed to allow him the £5.5m release clause. The clause "effectively removed [Middlesbrough] from the picture. [The club] was left with no choice; a choice which it would otherwise have had under the terms of the standard contract," the court found."
Although:-
"Blackburn's only recourse to compensation is based on United's knowledge of the £16m release clause – commercially confidential information which enabled them to bid at virtually the lowest price possible to trigger the sale of Jones. Rovers may negotiate a compromise with United, based on Jones' appearances and trophies United win with him, to avoid a drawn-out legal battle on this point. Middlesbrough pursued Liverpool through the courts on similar grounds, arguing that the buying club profited from confidential information to bid at Ziege's exact £5.5m release clause figure.
At the time, Middlesbrough alleged an illegal approach had been made to the player. The two sides settled out of court with the Premier League acting as a mediator.
Blackburn's case is complicated by the fact that it needed Venky's' football advisers to resolve the weekend's impasse by making the contractual situation clear to the Indians – namely, that the release clause had been inserted into Jones' contract when he agreed an extension to his terms in February."
Don't quite understand why Blackburn's case is complicated but sure United can get over this confidential information thing.
It is not illegal to be told confidential information. Sure they can argue:-
1. His agent told United once Liverpool had made a bid
2. Read it in the media
3. Share same/similar agents (don't know if it's true)
4. News spread once Liverpool/Spurs/Arsenal were involved.
5. Someone at BRFC told them.
6. any others? - write them hear and help our lawyers out...