When I read the obit, I was surprised to learn some of the background behind this song and Len Barry. There was a lawsuit about this song filed by Motown, who claimed the song was based on one of their songs. The arrangement of the song, with horns and vibes, has similarities to the Motown song. It was recorded in NYC, with some established jazz musicians, including Freddie Hubbard on trumpet. The result of the Motown suit was the writers of "1-2-3," one of which is Len Barry himself, had to share a percentage of the publishing royalties with Motown.