David Bowie learned about the music business the hard way: from a notoriously bad contract with early manager Tony Defries that reportedly gave him half of the singer’s earnings. They parted ways in 1975, in a deal that gave Defries -- who paved the way for Bowie’s rise to superstardom -- a share of some of the singer’s income for the following seven years. 

Bowie then took control of his career with a vengeance, managing himself with the same adventurous, even visionary, spirit that he brought to his music. He explored different musical genres and owned his recordings, embraced both drum n’ bass and an innovative bond deal that let him borrow money against income from future royalties.

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Defries helped make one key business decision that played a large role in allowing Bowie to take charge of his career: He negotiated the singer's 1970s RCA deals so the two would own the recording copyrights, a provision almost unheard of at the time. At the time, no one knew how valuable the rights to recordings would become -- or how important Bowie’s would be. According to Billboard's estimates, his recordings and publishing rights are now worth about $100 million -- and likely even more. 

In 1983, after his deal with RCA expired, Bowie signed a global contract with EMI for a reported $17.5 million that covered his new recordings, starting with the blockbuster album Let’s Dance. After that deal ended, he signed a series of short-term contracts, first with Victory Music for 1991's Tin Machine II, then to the BMG-distributed Savage for 1993's Black Tie White Noise. He then signed with Virgin Records, a division of EMI, in a deal that, like all of his contracts since the 1970s, allowed him to control his recordings.

In 1989, Bowie licensed his RCA catalog -- 1969’s Space Oddity though 1980’s Scary Monsters (And Super Creeps) -- to Rykodisc, then an independent label focused on CD reissues. 

“He wanted to control where and when his music was used -- his pride in that was important,” Bill Zysblat, Bowie’s business manager since 1982, tells Billboard. “It was never about money. It was always about doing the newest thing, doing the coolest thing.” 

In 1990, Bowie promoted the Rykodisc reissues with his Sound+Vision tour, marketed as the final time he would perform his older hits. (He subsequently changed his mind.) He also became one of the first artists to have one promoter handle an entire tour -- a strategy he stuck with. The tour after that, and every one since, were promoted by Arthur Fogel, now chairman of Live Nation’s global touring division. “Having one person with a global view, compared to individual promoters only worried about their local markets, is invaluable,” Bowie told Billboard in 2005. 

After the Rykodisc deal ran its course, Bowie licensed his albums to EMI Music for a reported advance of $30 million. As part of the same 1997 deal, Bowie also acquired Defries’ share of his recordings and issued $55 million in bonds backed by royalties from album sales and publishing rights, the lion's share of which the singer also owns or co-owns. (The rights to all of his albums except for the last four are now licensed to Warner Music.)

“He understood the concept in a split second,” says David Pullman, who put together the bond deal, among the first to securitize copyright royalties. “He never complained, and he wasn’t afraid to fail.” 

All of the bonds, which paid an interest rate of 7.9 percent, were purchased by the Prudential Insurance Company of America. Although Moody’s downgraded the bonds in 2004, due to weakening overall album sales, all of the payments were made either early or on time. Since the Bowie deal, the Pullman Group has issued bonds based on royalties due the Motown songwriting team Holland-Dozier-Holland, the R&B and songwriting duo Ashford & Simpson, and the estate of Marvin Gaye. 

In the mid-1990s, Bowie became fascinated by the Internet and how technology would change the music business. In late 1996, he became one of the first major artists to release a song online when he made three versions of the single “Telling Lies” available on his official website. The following year, he “cybercast” a Boston concert -- a venture that was more visionary than practical given the technological limitations of the time. “He was very involved with technology at a time when most label people still thought the Internet was America Online,” says a music executive who worked with him then.  

Bowie also launched several online ventures. In 1998, through the company UltraStar, he started the dial-up online service provider BowieNet, which offered subscribers their own @bowienet email address. Although UltraStar didn’t last as an Internet service provider, the company became an online fan-club business that went on to work with the Rolling Stones and Madonna. In 2006, it was sold to Live Nation. 

“David was very involved in the direction of UltraStar -- he attended meetings and got involved in artistic decisions,” says Ron Roy, a partner in the venture. “Once exposed to the power of direct online communications between artists and fans, David realized that music was about to change forever.” 

In interviews, Bowie spoke of a time when artists would no longer need labels. “I don’t even know why I would want to be on a label in a few years because I don’t think it’s going to work by labels and by distribution systems in the same way,’’ he told The New York Times in 2002. “I’m fully confident that copyright, for instance, will no longer exist in 10 years, and authorship and intellectual property [are] in for such a bashing.” Around that time, he started his own label, Iso, distributed through Sony Music -- which has released his last four albums, as well as a 2010 live collection.

In 2013, the licenses to Bowie’s catalog were acquired by Warner Music Group, along with the rest of EMI’s Parlophone imprint. Late last year, Warner’s Rhino Records released Five Years (1969-1973), a box set of Bowie’s albums from those years, along with some rarities and two live collections. The label plans further box sets based on different eras of Bowie’s career, as well as various other reissues, including a vinyl edition of the BBC sessions collection Bowie at the Beeb, due late in February.

So what are Bowie’s recording and publishing rights worth today? Using the singer's 2015 U.S. album sales (152,000), track downloads (476,000), radio plays (87,000) on-demand streams (134,000,000), and a worldwide synchronization estimate of $2 million, according to industry-standard formulas, Bowie’s recordings and songs could have generated more than $8 million worldwide last year, including sales, streaming, performance and mechanical royalties, and synch royalties for the use of his music in films and television shows. The stage show based on his music, Lazarus, could generate even more revenue. 

But that represents just a fraction of his catalog’s total value. Recording and publishing catalogs of iconic artists are generally valued at 12 times annual revenue, which places Bowie's catalog at around $100 million -- and his merchandise and likeness rights have significant value on top of that.

Sadly, Bowie died just three days after he released his most recent album, Blackstar, which was garnering rave reviews even before his death. The album is expected to sell about 130,000 copies Stateside in its first week in stores, making it -- incredibly -- Bowie’s first-ever No. 1 album in the U.S. Sony Music shipped about 80,000 copies to retail outlets, and Rhino made sure Five Years was in stores -- but by Monday, Sony Music had run out of CDs to fill retail orders and Rhino was giving each store just a portion of the numbers they had ordered, leaving both companies rushing to catch up. 

Bowie's vast influence on popular music has been well documented, but his influence on the business around it has been almost as profound. 

“He saw how the digital age would affect copyrights and record companies,” says Zysblat. “The world doesn’t know how brilliant he was -- not only about music, but about history and technology.” 

An edited version of this story first appeared in the Jan. 23 issue of Billboard.