Before the current Tempest vs. Timbaland case, claims of plagiarism go a long way back in music. Here are some (and more or less random) brief examples from the history of popular music, though these are only the proverbial tip of the iceberg of all the cases where an artist or his/her record label has claimed someone else has stolen his/her music... In the current day of "postmodern", "retro" type of pastiche pop where "ironic" references and "appropriations" (or "homages") abound everywhere, maybe it's harder to speak about plagiarism in any traditional terms, so it's interesting to see how our ideas about this will change in time.
The Kinks successfully sued The Doors for plagiarizing their 'All Day and All of the Night' to 'Hello, I Love You' in 1968.
'Black Knight' (1970) by Deep Purple sounds very much like 'We Ain't Got Nothing Yet' by The Blues Magoos (of Nuggets) fame. Actually, Wikipedia says: "The riff to Deep Purple's 1970 'Black Night' single was closely based off the riff to Ricky Nelson's 1962 'Summertime' (Deep Purple have said this themselves). In fact, the riff is a popular one to borrow. In 1966/67 the Blue Magoos had 'We Ain't Got Nothing Yet' around the same time that Status Quo had own their version. But the riff seems to stem back to Ricky Nelson's 1962 rock version re-working of the old George Gershwin standard 'Summertime'".
George Harrison was sued for plagiarizing 'He's So Fine' by The Chiffons for his song 'My Sweet Lord' in a long-lasting law suit which started in 1971. Harrison was ordered to pay $587,000 to Bright Tunes Music (the owners of the song's copyright) in 1976, after a judge found him guilty of "subconscious" plagiarism. The Chiffons would later record 'My Sweet Lord' to capitalize on the publicity generated by the lawsuit.
Led Zeppelin used a riff from 'Taurus' by Spirit for their best-known song, 'Stairway to Heaven'. Spirit's guitarist Randy California was reportedly just happy to let Zeppelin to use the riff. Led Zeppelin was often also accused of using old blues songs uncredited as the basis of their own tracks. Also Bob Dylan has been accused along the years of "appropriating" old songs for his own tracks.
All unsold copies of 1987 (What the Fuck Is Going On?), the 1987 debut album of The Justified Ancients of Mu Mu (a.k.a. The KLF) were ordered to be destroyed by the Mechanical-Copyright Protection Society, following a complaint from ABBA; the JAMS having sampled large portions of ABBA's 'Dancing Queen' for the track 'Queen and I'.
De La Soul was sued by The Turtles members for featuring an uncredited sample (the intro to The Turtles' 'You Showed Me') in the song 'Transmitting Live from Mars' on De La Soul's 1989 debut album. This was one of the first court cases over sampling music.
Negativland issued in 1991 a single called 'U2', featuring parodies of the group U2's well-known song 'I Still Haven't Found What I'm Looking For', including kazoos and extensive sampling of the original song. U2's label Island Records sued Negativland and most copies of the single were recalled and destroyed.
For their 1997 track 'Bittersweet Symphony' -- using a licensed sample from the Andrew Oldham Orchestra's version of 'The Last Time' by The Rolling Stones (1965) -- The Verve (UK) was sued by ABKCO Records of Allen Klein, which owns the rights to The Stones' 60s recordings. ABCKO claimed The Verve had used "too much" of the sample. The matter was eventually settled out of court, with copyright of the song (which lyrics were written entirely by The Verve vocalist, Richard Ashcroft) reverting to ABKCO and songwriting credits to Mick Jagger and Keith Richards of The Stones.
Splank of Zombie Nation had to pay an undisclosed amount to David Whittaker, the programmer who wrote the original music riff to 80s Commodore-64 computer game 'Lazy Jones', which was used as the basis of Zombie Nation's 1999 hit 'Kernkraft 400'.
It is now claimed that Janne Suni a.k.a. Tempest a.k.a. Damage, a Finnish demoscene musician/graphic artist (who has also done cover art for Jyväskylä's Rikos Records), has had 'Acid Jazzed Evening', one of his tracks, blatantly ripped by the well-known hip-hop/R&B producer Timbaland on Nelly Furtado's song 'Do It' for her album Loose.
The said track is from a Commodore 64 conversion of an Amiga .mod file made by the Finnish demoscener Janne Suni. The track was entered into a music competition at Assembly 2000, a demo party held in Helsinki, Finland in the year 2000. Tempest's entry 'Acid Jazzed Evening', a 4-channel Amiga .mod won first place in the "Oldskool Music" competition. According to Scene.org the song was uploaded to their servers in 2000, long before the release of the song by Furtado. A video which claims to show proof of the theft was posted to YouTube on January 12, 2007. It's yet unknown whether Janne Suni will ever be able take the case to the court, the prospects of winning a court case against a major record label-backed international celebrity artist being very slight; not to talk about any astronomical expenses involved in losing a case like that.
I remember the Jaguar case caused a very angry response in dance music community towards Sony/BMG and generated lots of negative publicity, so similarly I think now only a massive media exposure and pressure from fellow musicians/music fans/journalists etc. all over the world might help Tempest/Janne Suni getting his due compensation here.
As it was pointed out in media articles above, any court case against Timbaland and his multinational record label (with their mighty army of highly-paid corporate lawyers; just remember the OJ Simpson case...) would probably be lost (as said, not to talk about another additional injury caused by the case's expenses) by Tempest or anyone representing him. So it seems to me some sort of out-of-court settlement would be the only realistic outcome here.