Bruce Springsteen fans treated to a special New York set last month were unaware of the career-defining moment taking place off stage.
Just a day after he joined Steve Earle and The Dukes for a charity performance, The Boss unveiled a $500m (£369m) music rights sale that cemented his place in rock's hall of fame.
By offloading his master recordings and publishing rights to Sony Music, the singer behind era-defining albums such as Born to Run and The River sealed the largest ever sale of one artist's work.
For those inside the music industry, the transaction will have come as no surprise. It was simply the latest in a welter of deals for artist and producer royalties that helped the value of music mergers and acquisitions reach record heights in 2021.
Nearly $13bn (£10bn) was spent last year, up from $5bn in 2020 according to data from MIDiA Research, with the boom expected to continue as private equity and pension funds pile in.
The huge deals are an example of supply and demand working in perfect harmony. Music investment funds eager to transform the hits of yesteryear into a new asset class have been prowling the market as they seek to capitalise on the consistent returns delivered by music streaming.
Meanwhile, the pandemic-induced prohibition on live music, the prospect of a US capital gains tax hike on song rights sales of more than $1m and the meagre returns some artists make from streaming compared to traditional records have prompted many to cash in.
Hipgnosis, the London-listed fund spearheaded by former Elton John manager Merck Mercuriadis, has secured music rights to Shakira, Red Hot Chili Peppers and Bon Jovi.
Bob Dylan has sold his catalogue to Universal Music, while BMG, the Bertelsmann-owned record label, bought Tina Turner's back catalogue in October. That swoop was swiftly followed with a $150m deal for the song royalties of the heavy metal band Motley Crew.
David Bowie's estate, worth more than $200m, could be next to follow as Warner Music eyes the Thin White Duke’s songwriting catalogue.
Kriss Thakrar, an analyst at MIDiA , says a new round of investment is now gearing up to target latter-day hits.
"There’s an investor narrative that streaming is creating this resurgence of revenue for classic hits, which is why a lot of the biggest deals are for older rock artists, as much of the demand is competing for the same supply," he adds.
"However, there are a lot of more modern catalogues that have a lot of unrealised potential in the pop, hip hop and the R&B space."
Private equity is also hoping to take a slice of the steady, long-term, returns delivered by songbooks in an era of low interest rates.
Music to investors' ears
But the vast sums of money at the industry's fingertips have only taken it so far. While buy-out barons across the world are thought to have more than $1 trillion (£740bn) of dry-powder at their disposal, they lack the industry contacts needed to put this money to work.
The web of connections woven by Mercuriadis whilst boss of Sanctuary Records has given him a head start. Not only does he know which artists are willing to give up their rights, but they trust him to protect their legacies.
These hurdles have prompted private equity to partner with record labels and music investment funds insread of going to war with them.
BMG, the record label behind Nirvana and Kylie Minogue, teamed up with KKR in March. Both parties benefited: BMG secured greater financial firepower, while the buy-out behemoth gained more exposure to rights deals.
And they are not alone. Mercuriadis has partnered with Blackstone to invest $1bn on music rights that will see the fund co-invest with Hipgnosis.
With pension funds also poised to begin moving into the market, more co-investment partnerships are expected in 2022 as the asset class matures.
Mercuriadis explains why the music investment funds have gained the upper hand so far: "What separates us from almost all of our competitors is our access and relationships with the greatest songwriters in the world.
"As a result approximately 70pc of our deals are private off-market transactions where we are not competing."
Marrying such expertise with vast walls of capital will intensify competition, causing valuations to soar. The move is expected to hasten the evolution of the music investment market, prompting more music-linked financial products to emerge.
Speculation is already mounting that music bonds could make a prominent return nearly 24 years after Bowie securitised the rights of his royalties.
Return of Bowie Bonds?
Those financial products - known as Bowie Bonds - were linked to Let's Dance singer's American rights, and offered a fixed annual return of 7.9pc over 10 years.
With Kings of Leon also selling their latest album When You See Yourself as a non-fungible token (NFT), the opportunities to cash-in are multiplying.
Mark Mulligan, the managing director of MIDiA, believes all the ingredients are in place for another royalties investment boom this year.
"We have a constrained supply market and an increased demand from all these funds that have raised money that they are going to deploy," he says.
"That means prices will go up, there will be increased competition and what happened in 2021 will carry on through into 2022. You will probably see an increased sophistication in the segmentation of the market, with lots of derivatives and financial products.
"We will see the same thing happen to music as an asset class, as we have seen happening to other asset classes. More big funds - like pension funds - will look to add music to their portfolios as well."
Such conditions suggest Springsteen will not have to wait long before his deal is blown out of the water by another huge investment.
After all, the singer is just one of many ageing rockers contemplating their legacy as the streaming revolution gathers pace.
Many will take comfort knowing their hits will remain popular long after they have passed.
And it is for that reason alone why the money chasing music rights is unlikely to subside anytime soon