By Paul Lewis
BBC Radio 4's Money Box
Standard Life says the information it gave was not misleading
A financial services lawyer says Standard Life material about its Pension Sterling Fund was "misleading."
He says the city regulator should be examining the fact sheets to consider if compensation should be paid.
Standard Life has already said it will compensate people who invested after it revalued the fund on 23 December.
But it insists "customer literature [showed] the fund was invested... in a range of short dated money market instruments."
However, documents seen by BBC Radio 4's Money Box programme show that in March 2008 a fact sheet issued by Standard Life showed 100% of the fund - sold as a safe harbour for pension money shortly before retirement - was in cash.
And Standard Life has admitted that up to 40% of the fund is still held in what are called "mortgage backed securities" - the products which have been involved in the subprime banking crisis which has swept around the world.
Adam Samuel, a lawyer who advises companies on whether their product information conforms to regulations, which say it must be "clear, fair and not misleading" told Money Box the documents failed that test.
"There's a description of the asset type as being 100% in cash, which in the small print says could indicate some short term money market instruments.
"Mortgage backed securities tend to be over quite a long term so that's wrong.
"The documents are not clear, not fair and definitely misleading."
His comments were made a week after Standard Life told Money Box there were no grounds to compensate its customers.
Three days later it said it would compensate those who invested after it revalued the fund downwards on 23 December, but before it made that information public on 14 January.
Adam Samuel says the documents show there is a case for taking the compensation back much further.
"The Financial Services Authority should be sitting down with Standard Life and going through documentation for each year and deciding whether their descriptions of the fund pass the clear, fair and not misleading test.
"In reality that may mean compensating everybody."
Standard Life response
Standard Life told the programme that the information provided to customers was not misleading and in a statement said:
"It has been detailed in our customer literature that the fund was invested not only in deposits but also in a range of short-dated money market instruments.
"As soon as sufficiently reliable information was available, the securities held in the fund were revalued.
"That led to a reduction in the unit price."
The company would not comment in writing on the suggestion that compensation should be extended.
The FSA would not comment.
BBC Radio 4's Money Box was broadcast on Saturday,
24 January 2009 at 1204 GMT.