Simmons & Company International, a transatlantic corporate finance boutique that specialises in the oil and gas sector, is advising the private equity consortium led by Candover to clinch the long-awaited buy-out of an ABB unit.

This is Simmons' first European deal worth more than $1bn (€900m), according to Dealogic, the investment banking research firm, although it has completed a number of large deals in the US.