Shortly after our music locker service debuted, we got sued by all the major labels. I spent 4 months writing tools to pull all the discovery data for their lawsuits.
When it was apparent our court case was going south, the major music publishers sued us as well (lead by Harry Fox Agency). I spent another 4 months pulling discovery data for those lawsuits.
When those court cases trended badly for us, we got sued by every 2 bit operation that owned a partial percentage of the country-based rights to a song (ie, one company may of owned 4% the rights of a song in the United States and 10% in Mexico and 9.3% in Ireland, with another company owning 1.3%, 40%, .5% respectively). I spent another 4 months pulling discovery data for those lawsuits.
Finally, after we where acquired by Vivendi Universal and they took on our liabilities, I spent almost a year writing tools for them to pay these partial percentages. Have you ever had to split 1 cent via check between 3 parties? It's not fun.
Moral of this boring story is Spotify better win this fast and clean or they are in a world of pain; I can never get those 2 years of my life back.