“The irony is they used very big uncleared samples in all their early tracks,” said Chris Atkins, the Who Killed the KLF? director.
The Guardian has learned that lawyers on behalf of Drummond and the KLF told the film-makers they took any infringement “extremely seriously”.
He is confident that the KLF film – made in conjunction with James Corden’s production company Fulwell 73 – will ultimately be released with the music intact.
Drummond did respond to a request for comment on whether he backed the legal action.