Summary

Introduction

On 22 July 2005 the first and third Claimants ("C1" and "C3") entered into a Production Sharing Contract (the "PSC") with the Defendant ("D") in respect of two oil mining blocks offshore from Nigeria.

In due course D and C1 entered into a Sale and Purchase Agreement (the "SPA") dated 29 December 2011, and amended on 28 June 2012, by which D agreed to sell to C1 its interest in the blocks and the PSC, with completion on 28 June 2012.

The second Claimant ("C2") is the ultimate parent of C1 and C3. On 28 June 2012 and in connection with the SPA, C2 entered into three guarantees in favour of D, the "Adjustments Guarantee", the "Deferred Payments Guarantee" and the "Services Guarantee".

Under the SPA (as amended) the consideration payable to D comprised (a) an Escrow Amount of US$100 million, (b) Deferred Payments of US$150 million payable in 3 instalments and (c) Adjustments (which might be positive or negative).

Disputes arose between the parties and an arbitral tribunal was constituted. The arbitration is an LCIA arbitration with its seat in London. The tribunal comprises Mr Thomas Webster, Professor Julian Lew QC and Lord Hoffmann. These proceedings before the Commercial Court concern a Second Partial Award issued by the tribunal and dated 23 September 2015 ("the Award").