YouTube pulls songs from Adele, Nirvana, and others due to SESAC dispute

Some of the most watched and listened to music on YouTube and YouTube Music disappeared on Saturday, replaced by a short message:

Video unavailableThis video contains content from SESAC. It is not available in your country.

That is probably not what people expected when they tried to stream Adele's "Rolling in the Deep" or other songs from artists as varied as Kendrick Lamar, Britney Spears, Green Day, Kanye West, and Burna Boy.

This leaves two questions: what is SESAC, and when is the music coming back?

SESAC stands for the Society of European Stage Authors and Composers, which has been around since 1930 and, according to its website, "...currently licenses the public performance of more than 1.5 million songs on behalf of its 15,000+ affiliated songwriters, composers, and music publishers."

It's smaller than similar organizations like BMI and ASCAP, but SESAC lists many big-name artists in its portfolio. In 2017, it was acquired by the private equity firm Blackstone.

Answering the question of when the SESAC music ban on YouTube and YouTube Music will end, or even what music has been removed, is a little harder.