Max Martin
Karl Martin Sandberg, known professionally as Max Martin, (born 26 February 1971) is a Swedish music producer and songwriter. Raised in Sweden, he became a producer and songwriter in the mid 1990s after writing a string of hits for pop artists like the Backstreet Boys, Britney Spears, *NSYNC, Kelly Clarkson, Katy Perry, and Pink, Taylor Swift, among many others.