Bonelli Erede Pappalardo client Enel and German utility E.ON, advised by Perez-Llorca, have come together to carve up Endesa in what should be one of the final chapters of the 18-month saga to gain control of the Spanish utility company.
E.ON sensationally withdrew its €42bn (£28.4bn) offer for Clifford Chance client Endesa last night, just hours away from closing.
An E.ON statement read: "E.ON signed an agreement with Enel and Acciona in order to put an end to the uncertainty surrounding the takeover bid for Endesa.
"Therefore, E.ON will not carry out the takeover bid designed to acquire a majority stake in Endesa. This means that E.ON will not acquire the shares tendered on the basis of an acceptance level of less than 50 per cent and will renounce making a new takeover offer for Endesa in the next four years."
Under the terms of the agreement, Enel and Spanish construction group Acciona will be free to launch an offer for Endesa. Slaughter and May's best friends in Italy and Spain, Bonelli and Uría Menéndez respectively, teamed up to advise the pair, drafting in heavy-hitting name partners Sergio Erede and Rodrigo Uría.
If Enel and Acciona are successful in their bid, E.ON will then buy €10bn (£6.76bn) worth of current Endesa assets from them across Spain, Italy, France, Poland and Turkey.
The rapprochement between E.ON and Enel was in stark contrast to last month, when E.ON complained to Spain's market regulators, accusing Enel and Acciona of market disruption and insider trading.
E.ON had raised its offer for Endesa to €40 (£27.05) a share, which was immediately trumped by a joint bid proposed by Enel and Acciona worth €41 (£27.73) per share at the end of March.
Endesa has been advised by Clifford Chance since fellow Spanish company Gas Natural made its approach of €21(£14.20) a share in September 2005, sparking a bidding war with E.ON.