The surviving members of Led Zeppelin have all been questioned in a lawsuit that alleges their hit “Stairway To Heaven” was filched from an obscure song by the band Spirit, reports Bloomberg Business. Jimmy Page, John Paul Jones, and Robert Plant were each deposed separately over the past month as part of pretrial discovery in the copyright infringement case, new filings in Los Angeles federal court show.

During the depositions in London, they all said that they had no idea what their finances or earnings were with Led Zeppelin, according to a filing by the plaintiff's lawyer asking for more time to investigate. The musicians and their record company, Warner Music, deny the infringement allegations and say Plant and Page alone composed the 1971 song.

To many ears, the opening notes of “Stairway To Heaven” sound a lot like Taurus, an instrumental piece released on Spirit’s debut album in 1968 (decide for yourself here). At the end of that year and throughout 1969, Spirit and Led Zeppelin shared the bill at several concerts.

Led Zeppelin's guitarist, however, testified his memory of the era was vague, according to the filing by plaintiff's lawyer Francis Alexander Malofiy, who conducted the questioning. "Jimmy Page’s discovery answers [the] claim that he remembers virtually nothing about the 1960s or 1970s despite many public interviews concerning Spirit where he stated that he listened to the band’s albums and that they struck him on an emotional level, despite the fact that he played and attended concerts where Spirit performed," Malofiy wrote.

Read the full story at Bloomberg Business.