A US judge has rejected Ed Sheeran's call for a legal case accusing him of copying parts of Marvin Gaye's Let's Get It On to be dropped.
In his decision released on Thursday, District Judge Louis Stanton said a jury should decide.
He said he found "substantial similarities between several of the two works' musical elements".
Sheeran denies ripping off sections of the 1973 classic for his number one hit Thinking Out Loud.
The action has been brought against Sheeran, Sony/ATV Music Publishing and Atlantic Records by the estate and heirs of the late producer Ed Townsend, who co-wrote Let's Get It On with Gaye.
Judge Stanton is also overseeing a separate $100m case over the same track launched last June by the company Structured Asset Sales, which owns part of the copyright in Gaye's song.
Judge Stanton said the similarities between the two songs included their bass lines and percussion and said listeners might consider the songs' "aesthetic appeal" to be similar.
He said there was disagreement over whether the harmonic and rhythmic composition of Gaye's song was too common to merit copyright protection.
Jurors "may be impressed by footage of a Sheeran performance which shows him seamlessly transitioning" between the songs, Mr Stanton added.
Sheeran's defence team has argued that Thinking Out Loud is different because it has "sombre, melancholic tones, addressing long lasting romantic love" while Let's Get It On is characterised as a "sexual anthem".
Sheeran and the record companies have not yet responded to Judge Stanton's ruling.
Comparisons between songs
Mr Townsend's family were looking forward to the case being heard in court, their lawyer Pat Frank told Reuters.
They say that Sheeran and the record companies "copied the heart of Let's and repeated it continuously throughout Thinking", according to court papers filed in 2016.
In 2017 Sheeran settled a $20m copyright infringement claim against him in the US, over his hit song Photograph.
Songwriters Thomas Leonard and Martin Harrington had sued the singer in 2016, claiming his hit ballad had a similar structure to their song Amazing.
Also in 2017, the team behind TLC's 1999 single No Scrubs were given writing credits on Ed Sheeran's Shape of You. It came after critics and fans made comparisons between elements of the songs.