(UMG's market cap stands at EUR €41.73 billion today, or USD $44.1 billion at current exchange rates.)

Of course, company share price/market cap values can quickly fluctuate, especially in the unpredictable world of the music business.

(Spotify's burst in value this year has partly been propelled by a slashing of headcount and a pull-back in marketing spend, both of which have sent the company's profitability shooting upwards.)

Any way you cut it, the stats suggest that the two largest music rights companies jointly own shares in Spotify worth comfortably more than USD $5 billion as things stand.

If Universal or Sony did cash in their stakes, it would be a good news day for the artist community.

In 2018, Universal Music Group followed Sony in publicly pledging to share any proceeds from Spotify stock sales with its artists.

Later that year, UMG matched Sony in publicly agreeing that it would ignore any of its artists' unrecouped balances in these potential payouts.

However, six years on, UMG still hasn't sold any of its Spotify stock; its artists continue to wait on the possibility of banking a share of any resultant cash.

(To reiterate: Sony didn't merely 'allocate' this money to internal artist accounts and then pay off chunks of their unrecouped balances with it; it actually bypassed unrecouped balances and paid all eligible artists on its books a share of the cash.)