Activist hedge funds and other investors will have far less time to disclose when they amass significant stakes in companies under a new rule from the Securities and Exchange Commission.

The SEC will give fund managers just five days, compared with the prior requirement of 10 days, to report they’ve bought up 5% or more of a company’s stock. The regulations are intended to give other investors more transparency, the agency said in a statement Tuesday.

“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,” SEC Chair Gary Gensler said in the statement.

Hedge funds have raised concerns that the new rules would hurt their ability to hold corporate boards and executives accountable and push for changes to business strategies.

The final rule didn’t include a proposal that could have forced more investors to disclose beneficial ownership as a group, if one of them told others about plans to acquire significant shares in a company. That proposal drew heavy fire from the private-funds industry, which said it would chill investor activism.

Instead, the rule clarifies the existing legal standards rest on whether investors act in concert to potentially trigger a reporting requirement.

The final rule also clarifies when certain derivatives count toward the 5% threshold for triggering reporting requirements.

The new requirements will go into effect for some filers 90 days after publication in the Federal Register, the SEC said.

Bryan Corbett, president and chief executive officer of the Managed Funds Association, a trade group representing hedge funds and private equity firms, said the group remained concerned with accelerating the disclosures. He also took issue with some aspects of the rule that relate to cash-settled derivative securities.

(Updates with outside groups’ comments in ninth paragraph.)