Standard Life's chief executive, David Nish, has written to the Scottish money manager's customers explaining how it will protect their interests in the event of Scots voting for independence.
He says that it could transfer pensions, investments and other long-term savings held by UK customers to new regulated companies set up in England.
The aim would be to ensure that all transactions with customers outside of Scotland could continue to be in sterling, that the Westminster tax regime would apply to them, and that they would be subject to regulation and protection by City regulators and the Financial Services Compensation Scheme.
It will also say that it will consider what further steps may be necessary to serve Scottish customers, once it becomes clear how the Scottish economy will be managed as an independent state.
I am told this is a precautionary statement by Standard Life, and that it has not seen a surge in withdrawals of funds or inquiries since opinion polls showed a growing prospect of Scots' voting for separation from the rest of the UK.
Mr Nish's letter elaborates on a statement Standard Life made in its last annual report.