Allen & Overy (A&O) is set to bill more than twice the combined amount notched up by Clifford Chance and Bingham McCutchen as the restructuring of Marconi nears its conclusion.
A&O, Marconi's long-time legal adviser, is already expected to be paid £25m for its work on reorganising the embattled telecoms company.
Overall law firms' billings for the deal are understood to make up at least half of the total £77.8m Marconi set aside for advisory fees, as revealed in its draft scheme of arrangement, which was published on 18 March.
However, with another £17.8m up for grabs for implementing the scheme of arrangement, £6m is estimated to go to A&O, leaving the firm with a massive £31m fee bonanza for the work.
In comparison, Clifford Chance, which advised a syndicate of 27 banks, is expected to be paid around £10m, while Bingham McCutchen is believed to be in line for £5m.
While the draft scheme of arrangement limits the costs of restructuring to a period from March/April 2002 until the "effective date of the schemes" on 31 May, it is not clear if these costs include previous work undertaken by firms.
A&O and Clifford Chance have been involved on the deal since late 2001, when Marconi attempted to extend two bank facilities that were close to maturity.
This was before the bondholders, owed £1.7bn, were brought into negotiations and a wholesale reorganisation of Marconi began last March.