Songfacts®:

• This Dr. Luke produced ballad finds Katy with her sights set on a guy, and she won't take no for an answer. It was selected as a promotional single from Prism after the singer asked fans to choose between this song or the dance club heavy "Walking On Air."
• The song features a verse from Juicy J. The Memphis rapper told RapFix Live host Sway Calloway about their collaboration: "Dr. Luke gave me a call and was like, 'Hey man, Katy Perry wants you to feature on one of her songs for her album' and I was like, 'Wow.' I couldn't believe," he said. "He sent me the track over, I did the verse and like a week later he called me again and he was like, 'She wants to meet you she wants you to come to the studio.'"
  
  The recording process was something new for the rapper. "It was a little different. I did a lot of different versions to it. I recorded almost three verses because I wanted to make sure everything fit with the song and that she was satisfied," Juicy J said. "So it was a little challenging to make, but I've been doing this for a long time and I had fun doing it so it wasn't a problem."
  
  Dr. Luke also served as executive producer on Juicy J's Stay Trippy album.
• The term "Dark Horse" is used to describe a person whose abilities or possible course of action are unknown, or to a somebody who reveals unsuspected talent. The earliest-known use of the phrase was in novelist and future Prime Minister Benjamin Disraeli's 1831 novel The Young Duke: A Moral Tale Through Gay. He described a horse race where, "a dark horse, which had never been thought of... rushed past the grandstand in sweeping triumph."
• Uses of the term "Dark Horse" in popular music include a 1974 single, album and tour by George Harrison named after the phrase. The former Beatle also named his record label Dark Horse Records. In addition, Canadian rockers Nickelback gave their 2008 album the moniker of Dark Horse and Alternative rock band Switchfoot titled the first single off their 2011 Vice Verses "Dark Horses." A few years after Katy Perry dropped this song, country singer Devin Dawson named his debut album, Dark Horse. He closes his set every night with the title track.
• This song was co-penned by Sarah Hudson, who is a singer-songwriter and a member of the pop group Ultraviolet Sound. She isn't related to Katy (whose real name is Katy Hudson), however Sarah is the first cousin of another famous person with the same name: the actress Kate Hudson.
  
  Other writers listed on the track are Perry, Dr. Luke, Max Martin, Juicy J, and Cirkut.
• Perry revealed at a special album release party with iHeartRadio that the song was inspired by the 1996 movie The Craft, which is, "about warning a guy that if you're going to fall in love with me, make sure you're sure because if not, it's gonna be your last." The singer added that it reminded her of the moment she heard the Teenage Dream single "E.T.."
• The song finds Perry playing seductress and putting a potential lover under her spell. She described the lyrics to MTV News as "kind of witchy and dark, as if I was a witch warning this man not to fall in love with me, and if you do know I'm going to be your last." Perry went on to describe the tune as having a "witchy, spell-y kind of black magic-y idea."
• Along with Juicy J, Perry performed this song at the Grammy awards in 2014. She went with a witchcraft/enchanted forest theme, staging an elaborate spectacle where she emerged from a giant crystal ball and sang to an anthropomorphic horse. Those who believe in Illuminati found lots of evidence of Perry's involvement with the group in her performance.
• The song hit the top of the Hot 100 after Perry performed it on the Grammy Awards on the previous Sunday. "This #1 is the most unexpected one I've ever had," said the singer. "'Dark Horse' has been a dark horse of a song, since August when the KatyCats voted to release it early on iTunes, before PRISM even came out."
• Perry enlisted Matthew Cullen to helm the video in which she plays a mystic queen in ancient Egypt. The pair previously worked together before, on her "California Gurls" clip. Juicy J also appears in the visual, emerging from a mummy's sarcophagus.
• Members of the Muslim community criticized the video, citing the part around the 1:15 mark when Perry kills a male subject wearing a pendant that forms the word "Allah," the Arabic word for God. The jewelry is also destroyed.
  
  Following a petition, which was signed by more than 65,000 people, the pendant was digitally removed from the scene.
• Perry and the other songwriters were taken to court by Christian hip-hoppers Flame (Lecrae and John Reilly) for allegedly stealing the beat from their 2008 single "Joyful Noise." for this tune.
  
  The lawsuit claimed that the songwriters stole the track and presented it as their own. It was also alleged that Perry ruined the faith-based message of the song by creating a blasphemous video containing uses of witchcraft, idols and black magic. "The devoutly religious message of 'Joyful Nose' has been irreparably tarnished by its association with the witchcraft, paganism, black magic and Illuminati imagery evoked by the same music in 'Dark Horse,'" read the suit. "Indeed, the music video of 'Dark Horse' generated widespread accusations of blasphemy and an online petition signed by more than 60,000 demanding removal of an offensive religious image from the video."
  
  Flame took home a Gospel Music Association Dove Award for "Joyful Noise" while the LP it's from, Our World: Redeemed, won the Grammy for best rock or rap gospel album.
  
  On July 29, 2019, a nine-member federal jury found that "Dark Horse" was sufficiently similar to "Joyful Noise" to constitute copyright infringement. The plaintiffs were awarded $2.78 million in damages, of which Perry herself was ordered to pay $550,000.
  
  On March 17, 2020, the ruling was overturned on appeal, with the judge saying the passage in question was "not a particularly unique or rare combination."
  
  On March 10, 2022, The Ninth Circuit appeals court sided with Katy Perry. By a 3-to-0 vote, the jury upheld the overturning of the original decision, saying a verdict against Perry would have dangerous consequences for future creativity.
  
  A statement from the court of appeal read: "The portion of the 'Joyful Noise' ostinato that overlaps with the 'Dark Horse' ostinato consists of a manifestly conventional arrangement of musical building blocks. Allowing a copyright over this material would essentially amount to allowing an improper monopoly over two-note pitch sequences or even the minor scale itself."
• A YouTube video showing how this song stopped a baby crying went viral in August 2014 and renewed interest in the tune.
• This won Best Single at the 2014 American Music Awards. Perry also claimed the gongs for Favorite Pop/Rock Female Solo Artist and Favorite Adult Contemporary Artist at the same ceremony.
• The song's video was the most popular music clip on YouTube in 2014, with 715 million views. It was also the most-streamed song of the year if YouTube views are factored in.
• Sans Juicy J, Perry performed this song at the Super Bowl in 2015 when she was the halftime entertainment. For this part of the show, the stage was transformed into a giant chessboard, with Perry singing among an array of dancers in a postmodern, equine motif.
• The pooch that has a star turn in the video is Jiff, a Pomeranian from Los Angeles, California. Jiff once held two Guinness World Records: for the fastest 10-meter run on hind legs (6.56 seconds) and the fastest five-meter run on front paws at (7.76 seconds).