Ozzy and Sharon Osbourne may be splitting up after more than 33 years of marriage.
A spokesman for the couple said: "At this time Ozzy is not at the marital home."
The Black Sabbath frontman, 67, has fought a public battle with drug and alcohol addiction throughout their marriage.
He relapsed and this led to divorce rumours in 2013, but Sharon, 63, stood by her husband.
Reports suggest their current separation is not due to substance abuse issues.
Sharon, a former judge on ITV's The X Factor, detailed her reaction to her husband's relapse in her book, Unbreakable: My New Autobiography.
The star, who is a panellist on daytime US series The Talk, discovered he had relapsed as the couple celebrated 30 years of marriage.
"I would never have imagined our anniversary would be the start of one of the worst periods in our marriage," she wrote.
Ozzy and his wife met in the 1970s via her father Don Arden, who was managing the heavy metal group at that time. Sharon managed the Birmingham-born rocker before becoming his wife.
The pair wed in 1982 and have three children together: Jack, Kelly and Aimee. Ozzy also has three children from his previous marriage.
The Osbourne family found a new level of fame when, with the exception of oldest child Aimee, they appeared in a television series together.
The Osbournes, the popular MTV reality show revolving around their lives, ran from 2002 to 2005 and became an instant hit.
It made the Osbournes household names around the globe. As recently as last year, the family was in talks for a possible reboot of The Osbournes.