President Barack Obama, center, speaks as former Presidents Bill Clinton, left, and George W. Bush, right, listen in the Rose Garden at the White House in Washington Saturday, Jan. 16, 2010.
CNN  — 

The National Archives is looking into sending letters to all living former presidents and vice presidents, asking them to go through their records to ensure there are no classified materials, according to sources familiar with the matter.

Representatives for four former presidents have all so far told CNN they do not have any classified records in their possession after news that former Vice President Mike Pence had classified documents in his Indiana home. The representatives for former Presidents Bill Clinton, George W. Bush, Barack Obama and the late George H.W. Bush all told CNN that all classified records had been turned over to the National Archives upon leaving office.

The discovery of classified documents in Pence’s Carmel, Indiana, home was the third such case in recent months. Former President Donald Trump and current President Joe Biden have also been subject to scrutiny after classified material was found in their homes.

None of the former presidents’ representatives said they were conducting additional searches of homes or offices where documents could potentially be stored.

Instead, they reiterated the practices those leaders followed when departing the White House in 1993, 2001, 2009 and 2017.

“All of President Clinton’s classified materials were properly turned over to NARA in accordance with the Presidential Records Act,” said Clinton’s office.

Bush and Obama followed the same practice, their representatives said, turning over both classified and unclassified material to the National Archives.

The Archives continues to maintain physical and legal custody of those records, Obama’s office said.

George H.W. Bush immediately turned over all his papers, including his personal papers, when he left office. Then, at a later date, his personal papers were returned to him as the Archives sorted through everything, sources familiar with his presidential papers said.

A source familiar with the Archives told CNN that they did not remember former President Jimmy Carter finding any stray classified documents.

Former Vice President Dan Quayle confirmed to CNN that everything was turned over and he never had any issues with finding classified papers after he left office, and sources familiar with records of former Vice President Dick Cheney said he also turned everything over when he left the White House and is in compliance.

A spokesperson for former Vice President Al Gore said, “When leaving the White House in January 2001, Vice President Gore and his staff turned over materials to NARA in accordance with the Presidential Records Act. No classified materials have been discovered in the 22 years since VP Gore left public office.”

This story has been updated with additional details.