Mr Justice Buckley ruled in the High Court that the firm failed to notice a discrepancy in the share agreement signed by IML, requiring it to invest £5.5m over five years in Russian clothing manufacturer Bolshevichka.
The Russian government had earlier stipulated that such an investment should take place over three years, but a Moscow arbitration later declared the agreement invalid.
Coudert associate John Sheedy, now based in New York, handled the case, supported by a London partner.
The court has just assessed damages at 70 per cent of the value that would have been realised by IML had Coudert not acted negligently on the original £5.5m investment. Brooke North, IML’s solicitors, has engaged experts to assess what the final value of the investment would have been.