A new change in US Securities and Exchange Commission disclosure rules is cutting the time limit for activist hedge funds and other investors to report when they have acquired 5% or more of a company's stock, according to a report by Bloomberg.

In a statement issued on Tuesday, the SEC confirmed it will give fund managers just five days, compared with the prior requirement of 10 days, to make the disclosers in a bid to give other investors more transparency.

SEC Chair Gary Gentler said in the statement: “In our fast-paced markets, it shouldn’t take 10 days for the public to learn about an attempt to change or influence control of a public company.”

The final, which rule also clarifies when certain derivatives count toward the 5% threshold for triggering reporting requirements, will come into effect for some businesses 90 days fear publication in the Federal Register.

Hedge funds though have raised concerns that the new rules will lessen their ability to hold corporate boards and executives top account for their actions and push for changes to business strategies.

Bray Corbett, President and Chief Executive utile Officer of hedge fund industry representative body the Managed Funds Association, said in a statement that "MFA remains concerned with the Commission’s justification for moving notification from 10 days to five business days, cost-benefit analysis, and guidance included in the final rule regarding cash-settled derivative securities and group definition”.