On Tuesday, The Guardian reported that the Federal Bureau of Investigation (FBI) has changed its rules regarding how it redacts Americans’ information when it takes international communications from the National Security Agency’s (NSA) database. The paper confirmed the classified rule change with unnamed US officials, but details on the new rules remain murky.

The new rules, which were approved by the secret US Foreign Intelligence Surveillance Court (FISC), deal with how the FBI handles information it gleans from the National Security Agency (NSA). Although the NSA is technically tasked with surveillance of communications involving foreigners, information on US citizens is inevitably sucked up, too. The FBI is then allowed to search through that data without any “minimization” from the NSA—a term that refers to redacting Americans’ identifiable information unless there is a warrant to justify surveillance on that person.

The FBI enjoys privileged access to this information trove that includes e-mails, texts, and phone call metadata that are sent or received internationally. Recently, the Obama administration said it was working on new rules to allow other US government agencies similar access to the NSA’s database.

But The Guardian notes that the Privacy and Civil Liberties Oversight Group (PCLOB), which was organized by the Obama administration in the wake of the Edward Snowden leaks, took issue with how the FBI accessed and stored NSA data in 2014.

"As of 2014, the FBI was not even required to make note of when it searched the metadata, which includes the ‘to' or ‘from' lines of an e-mail,” The Guardian wrote. "Nor does it record how many of its data searches involve Americans’ identifying details."

However, a recent report from PCLOB suggested that the new rules approved by FISC for the FBI involve a revision of the FBI's minimization procedures. Spokespeople from both the FBI and PCLOB declined to comment on that apparent procedure change, saying it was classified, but PCLOB’s spokesperson, Sharon Bradford Franklin, told The Guardian that the new rules "do apply additional limits.”

A spokesperson for the Office of the Director of National Intelligence said that the new procedures may be publicly released at some point.