"I think it’s an absolute disgrace that the regulators have allowed UK investors to be eight years behind the standards in the US," said Miller. "The argument you always hear is that if you publish the data people will go out and replicate the manager’s funds, but how many investors are really going to go out and replicate 120 holdings? It is utter nonsense."
All US-domiciled funds have to report 100 per cent of their holdings every three months and the information is published on the website of Finra, the US equivalent of the FSA.
UK funds need only report all their holdings every six months, however, and there is no requirement for them to be published online.
A spokesman for the IMA disputed the level of difference between requirements, pointing out that the US information was difficult to find on the Finra website and questioning whether the two extra reporting dates a year were significant.
He added: "We have no evidence there is a desire for further disclosure. We think the information is effectively as accessible as in the US."
However, Miller claims that fuller disclosure could help prevent a repeat of the Arch Cru scandal, which led to many investors being mis-sold high-risk funds and having to resort to legal action to withdraw their money.
"If investors had been able to see 25 per cent of their money was in an unquoted Greek shipping company they might have decided to take it out. If you reveal to investors exactly what they own it gives them more confidence," he said.
He is also adamant that the requirement to publish online is critical rather than sending the information in the post, given that it makes the information freely available to all.
"The US regulators spotted 10 years ago there was this thing called the internet, but it seems the UK regulators have yet to catch up," he said.
The retail distribution review (RDR) has been designed to promote more transparency in the industry, and AWD Chase de Vere’s Patrick Connolly says that it is evidence of a move in the right direction.
However, he warned that over-regulation could harm the performance of funds and therefore ultimately investors’ interests.
"It’s very difficult to argue against transparency and as investors, we say the more information is available the better. However, the flipside is that we have to make sure it doesn’t become overly burdensome for the fund managers," he added.
"Where we are right now doesn’t seem too far away from the right place."
The FSA was unavailable for comment.