The company previously owned half of the publishing giant, but has now officially inhaled the other 50% after a $750m deal with prior controller the Jackson Estate.
The acquisition was cleared in Europe in August without any conditions.
Martin Bandier, Chairman and CEO, of Sony/ATV, said: “The completion of this deal is terrific news for Sony/ATV and everyone who works for the company.
“It marks the start of an exciting new chapter in our proud history and we cannot wait to get started as a 100% Sony-owned company. Sony Corporation has shown absolute faith and support in us and what we do by undertaking this deal and we are ready to repay that trust in the months and years ahead.
“The completion of this deal is terrific news for Sony/ATV and everyone who works for the company.”
Martin Bandier, Sony/ATV
“I’d also like to take a moment to thank the Estate and especially John Branca, John McClain and Karen Langford for everything they have done for Sony/ATV over the two decades of the joint venture. They will remain an integral part of our legacy.”
By finalizing the Jackson Estate deal, Sony becomes the third major to take full global control of a publishing company after Warner Music Group (Warner/Chappell) and Universal Music Group (Universal Music Publishing Group).
MBW revealed earlier this year that Sony/ATV was already by far the biggest publisher in the world in terms of the volume of copyrights it controls.
Across both its own repertoire and its administration of the catalogue of EMI Music Publishing, Sony manages over 4.2m songs.
Music Business Worldwide