What is John Mellencamp's middle name?

John Cougar Mellencamp

https://en.wikipedia.org/wiki/John_Mellencamp
http://www.imdb.com/name/nm0577908/bio

Cougar was a marketing strategy employed by the record company because Mellencamp was not "cool". Once established, John segued into his birth name via John Cougar Mellencamp, ultimately phasing out the "Cougar" part entirely. He did NOT like the "Cougar" crud from the get-go!

"John Mellencamp was born Oct. 7, 1951, in Seymour, Ind. He survived an early phase as a glam-rocker to become one of America's most successful mainstream rock singers of the 1980s. After playing in a local band, he was signed by David Bowie's manager Tony de Fries to a recording deal with MainMan in 1976. His name was changed to Johnny Cougar, and he was given a James Dean-style image... The following year, the singer changed his billing to John Cougar Mellencamp, and his chart successes continued with Uh-Huh in 1983 and Scarecrow in 1985... Moving to Mercury Records, the 1987 album Lonesome Jubilee used fiddles and accordions to illustrate bleak portraits of America in recession, while "Pop Singer" from 1989's Big Daddy expressed his disillusionment with the music business. In addition to ditching the "Cougar" nickname, he then took time off to concentrate on painting but returned with Whenever We Wanted in 1991, which recaptured the muscular rock sound of his earlier albums."

http://www.cmt.com/artists/az/mellencamp_john/bio.jhtml

NO middle name!

He has the initial J between John and Mellencamp. Apparently this stood for nothing.

Q: I’ve seen John’s name in print as both “John Jay Mellencamp” and “John J Mellencamp”. Which is correct?
A: Well, Tony Buechler (webmaster of Mellencamp.com) spoke to John's sister, Janet, at the Louisville show on 7/14/99, and she set the record straight. According to her, the "J" stands for nothing. So, John J Mellencamp would be correct.

https://www.angelfire.com/in2/infamousproductions/faq.html