As the two-year anniversary of Lehman Brothers' bankruptcy approaches, a potentially decisive encounter has been playing out behind closed doors this week at the UK's Pensions Regulator. At stake is the cash owed to around 2,400 former London staff who are members of the ex-bank's pension scheme.

The £180m pension scheme was in deficit when the bank collapsed on September 15 2008, possibly to the tune of around £100m - though that figure has probably changed a bit since then, for better or worse.