Harrison had been under contract to Northern Songs as a songwriter, but had a greatly reduced royalty rate compared to John Lennon and Paul McCartney. The Northern Songs contract expired in March 1968, giving Harrison and Ringo Starr the opportunity to make more money on the publication of their own compositions.
The reasons for the formation of Singsong are unclear. The company only published one song, Old Brown Shoe, before it and Harrisongs were combined. Harrisongs then published all of Harrison's later Beatles songs and his early solo works after the group's split.
Harrisongs' headquarters is at 27 Ovington Square in London, where Apple Corps is also based. The company also publishes songs by Harrison's son Dhani's group thenewno2.