The collapse of Lehman looks set to leave Songbird Estates, the Aim-listed owner of Canary Wharf, with almost 1m sq ft of unlet space.
Lehman occupies around 1m sq ft of 25-30 Bank Street, which was purpose-built for the investment bank and opened in 2003.
The building, the failed bank's European HQ, was valued at £955m at the end of 2007.
Lehman, which employed 4,000 people in the UK, pays an average annual rent of £41 per sq.ft as part of a 30-year lease - though property agents say the a rent review was imminent. The rent was expected to increase to £50 per sq.ft.
A vacancy of such size would provide a rare opportunity in London.
However, agents warned that there are a limited number of companies who will require the space that Lehman did, and so the future for 25 Bank Street appears uncertain.
But Canary Wharf does have a degree of protection from Lehman's withdrawal.
As part of the agreement with Lehman, it had a four-year "insurance policy" underwritten by AIG, which effectively means the American insurer would pay the lease for four years in the event that Lehman could not pay it.
The Daily Telegraph