The London office of US firm McDermott Will & Emery has become the latest law firm to be stung by the demise of Linklaters’ trophy client Cognition after admitting that it is owed substantial fees.

Cognition ceased trading in London last month and has refused to pay Linklaters the legal bill for its aborted £1bn flotation. The Linklaters bill is understood to have stood at £750,000 – £250,000 more than initial estimates.