The fire that swept across the backlot of Universal Studios Hollywood on Sunday, June 1, 2008, began early that morning, in New England. At 4:43 a.m., a security guard at the movie studio and theme park saw flames rising from a rooftop on the set known as New England Street, a stretch of quaint Colonial-style buildings where small-town scenes were filmed for motion pictures and television shows. That night, maintenance workers had repaired the roof of a building on the set, using blowtorches to heat asphalt shingles. They finished the job at 3 a.m. and, following protocol, kept watch over the site for another hour to ensure that the shingles had cooled. But the roof remained hot, and some 40 minutes after the workers left, one of the hot spots flared up.

The fire moved quickly. It engulfed the backlot’s famous New York City streetscape. It burned two sides of Courthouse Square, a set featured in “Back to the Future.” It spread south to a cavernous shed housing the King Kong Encounter, an animatronic attraction for theme-park visitors. Hundreds of firefighters responded, including Universal Studios’ on-site brigade. But the fire crews were hindered by low water pressure and damaged sprinkler systems and by intense radiant heat gusting between combustible structures.

Eventually the flames reached a 22,320-square-foot warehouse that sat near the King Kong Encounter. The warehouse was nondescript, a hulking edifice of corrugated metal, but it was one of the most important buildings on the 400-acre lot. Its official name was Building 6197. To backlot workers, it was known as the video vault.

Shortly after the fire broke out, a 50-year-old man named Randy Aronson was awakened by a ringing phone at his home in Canyon Country, Calif., about 30 miles north of Universal City, the unincorporated area of the San Fernando Valley where the studio sits. Aronson had worked on the Universal lot for 25 years. His title was senior director of vault operations at Universal Music Group (UMG). In practice, this meant he spent his days overseeing an archive housed in the video vault. The term “video vault” was in fact a misnomer, or a partial misnomer. About two-thirds of the building was used to store videotapes and film reels, a library controlled by Universal Studios’s parent company, NBCUniversal. But Aronson’s domain was a separate space, a fenced-off area of 2,400 square feet in the southwest corner of the building, lined with 18-foot-high storage shelves. It was a sound-recordings library, the repository of some of the most historically significant material owned by UMG, the world’s largest record company.

Aronson let the phone call go to voice mail, but when he listened to the message, he heard sirens screaming in the background and the frantic voice of a colleague: “The vault is on fire.”

Aronson dressed and steered his car to Interstate 5. A few minutes later, the air picked up a harsh scent: the acrid odor of the fire, riding the early-morning breeze into Santa Clarita, roughly 20 miles from the backlot. Aronson sped south. When he turned onto the Hollywood Freeway, he saw clouds of greenish-black smoke pouring into the sky. It was 5:45 a.m. when he gained access to the lot and made his way to the vault.

There, he found an inferno. Fire was blasting out of the building as if shot from giant flamethrowers. The heat was extraordinary. There were at least a dozen fire engines ringing the vault, and as Aronson looked around he noticed one truck whose parking lights seemed to be melting.

The vault lay near Park Lake, a man-made body of water that appeared in the classic B-movie “Creature From the Black Lagoon.” Fire crews began drafting water from the lake. They rained water from the tops of ladders; they doused the building with foam fire retardant. These efforts proved futile. “It was like watching molten lava move through the building,” Aronson remembers. “Just a huge blob of fire that flowed and flowed.”

Before long, firefighters switched tactics, using bulldozers to knock down the burning warehouse and clear away barriers to extinguishing the fire, including the remains of the UMG archive: rows of metal shelving and reels of tape, reduced to heaps of ash and twisted steel. Heavy machinery was still at work dismantling the building as night fell. The job was finished in the early morning of June 2, nearly 24 hours after the first flames appeared.

The fire made news around the world, and the destruction of the video vault featured prominently in the coverage. But nearly all news outlets characterized the vault fire as a close call, in which worst cases were averted. The New York Times reported that “a vault full of video and television images” had burned up, but added that “in no case was the destroyed material the only copy of a work,” a claim attributed to Universal Studios officials. Subsequent articles focused on the fire’s impact on film festivals, which relied on prints from Universal’s library. But journalists moved on from the story, and there has never been a full accounting of film and video losses in the fire.

The Times’s report was typical in another way: It contained no mention of a music archive in the devastated warehouse. The confusion was understandable. Universal Studios Hollywood was a movie backlot, not a record-company headquarters. What’s more, a series of mergers and acquisitions had largely severed the ties between Universal’s film and music businesses. In 2004, Universal Studios was purchased by General Electric and merged with G.E.’s television property, NBC, to become NBCUniversal; UMG was cast under separate management, and in 2006 fell wholly under the ownership of Vivendi, the French media conglomerate. When the fire struck in June 2008, UMG was a rent-paying tenant on NBC Universal’s lot.

One of the few journalists to note the existence of the UMG archive was Nikki Finke, the entertainment-industry blogger and gadfly. In a Deadline.com post on the day of the fire, Finke wrote that “1,000’s of original ... recording masters” might have been destroyed in the warehouse, citing an anonymous source. The next day Finke published a “clarification,” quoting an unnamed representative from the record company: “Thankfully, there was little lost from UMG’s vault. A majority of what was formerly stored there was moved earlier this year to our other facilities. Of the small amount that was still there and waiting to be moved, it had already been digitized so the music will still be around for many years to come.” The same day, in the music trade publication Billboard, a UMG spokesperson again pushed back against the idea that thousands of masters were destroyed with a more definitive denial: “We had no loss.”

These reassuring pronouncements concealed a catastrophe. When Randy Aronson stood outside the burning warehouse on June 1, he knew he was witnessing a historic event. “It was like those end-of-the-world-type movies,” Aronson says. “I felt like my planet had been destroyed.”

The archive in Building 6197 was UMG’s main West Coast storehouse of masters, the original recordings from which all subsequent copies are derived. A master is a one-of-a-kind artifact, the irreplaceable primary source of a piece of recorded music. According to UMG documents, the vault held analog tape masters dating back as far as the late 1940s, as well as digital masters of more recent vintage. It held multitrack recordings, the raw recorded materials — each part still isolated, the drums and keyboards and strings on separate but adjacent areas of tape — from which mixed or “flat” analog masters are usually assembled. And it held session masters, recordings that were never commercially released.

UMG maintained additional tape libraries across the United States and around the world. But the label’s Vault Operations department was managed from the backlot, and the archive there housed some of UMG’s most prized material. There were recordings from dozens of record companies that had been absorbed by Universal over the years, including several of the most important labels of all time. The vault housed tape masters for Decca, the pop, jazz and classical powerhouse; it housed master tapes for the storied blues label Chess; it housed masters for Impulse, the groundbreaking jazz label. The vault held masters for the MCA, ABC, A&M, Geffen and Interscope labels. And it held masters for a host of smaller subsidiary labels. Nearly all of these masters — in some cases, the complete discographies of entire record labels — were wiped out in the fire.

The scope of this calamity is laid out in litigation and company documents, thousands of pages of depositions and internal UMG files that I obtained while researching this article. UMG’s accounting of its losses, detailed in a March 2009 document marked “CONFIDENTIAL,” put the number of “assets destroyed” at 118,230. Randy Aronson considers that estimate low: The real number, he surmises, was “in the 175,000 range.” If you extrapolate from either figure, tallying songs on album and singles masters, the number of destroyed recordings stretches into the hundreds of thousands. In another confidential report, issued later in 2009, UMG asserted that “an estimated 500K song titles” were lost.

The monetary value of this loss is difficult to calculate. Aronson recalls hearing that the company priced the combined total of lost tape and “loss of artistry” at $150 million. But in historical terms, the dimension of the catastrophe is staggering. It’s impossible to itemize, precisely, what music was on each tape or hard drive in the vault, which had no comprehensive inventory. It cannot be said exactly how many recordings were original masters or what type of master each recording was. But legal documents, UMG reports and the accounts of Aronson and others familiar with the vault’s collection leave little doubt that the losses were profound, taking in a sweeping cross-section of popular music history, from postwar hitmakers to present-day stars.

Among the incinerated Decca masters were recordings by titanic figures in American music: Louis Armstrong, Duke Ellington, Al Jolson, Bing Crosby, Ella Fitzgerald, Judy Garland. The tape masters for Billie Holiday’s Decca catalog were most likely lost in total. The Decca masters also included recordings by such greats as Louis Jordan and His Tympany Five and Patsy Cline.

The fire most likely claimed most of Chuck Berry’s Chess masters and multitrack masters, a body of work that constitutes Berry’s greatest recordings. The destroyed Chess masters encompassed nearly everything else recorded for the label and its subsidiaries, including most of the Chess output of Muddy Waters, Howlin’ Wolf, Willie Dixon, Bo Diddley, Etta James, John Lee Hooker, Buddy Guy and Little Walter. Also very likely lost were master tapes of the first commercially released material by Aretha Franklin, recorded when she was a young teenager performing in the church services of her father, the Rev. C.L. Franklin, who made dozens of albums for Chess and its sublabels.

Virtually all of Buddy Holly’s masters were lost in the fire. Most of John Coltrane’s Impulse masters were lost, as were masters for treasured Impulse releases by Ellington, Count Basie, Coleman Hawkins, Dizzy Gillespie, Max Roach, Art Blakey, Sonny Rollins, Charles Mingus, Ornette Coleman, Alice Coltrane, Sun Ra, Albert Ayler, Pharoah Sanders and other jazz greats. Also apparently destroyed were the masters for dozens of canonical hit singles, including Bill Haley and His Comets’ “Rock Around the Clock,” Jackie Brenston and His Delta Cats’ “Rocket 88,” Bo Diddley’s “Bo Diddley/I’m A Man,” Etta James’s “At Last,” the Kingsmen’s “Louie Louie” and the Impressions’ “People Get Ready.”

The list of destroyed single and album masters takes in titles by dozens of legendary artists, a genre-spanning who’s who of 20th- and 21st-century popular music. It includes recordings by Benny Goodman, Cab Calloway, the Andrews Sisters, the Ink Spots, the Mills Brothers, Lionel Hampton, Ray Charles, Sister Rosetta Tharpe, Clara Ward, Sammy Davis Jr., Les Paul, Fats Domino, Big Mama Thornton, Burl Ives, the Weavers, Kitty Wells, Ernest Tubb, Lefty Frizzell, Loretta Lynn, George Jones, Merle Haggard, Bobby (Blue) Bland, B.B. King, Ike Turner, the Four Tops, Quincy Jones, Burt Bacharach, Joan Baez, Neil Diamond, Sonny and Cher, the Mamas and the Papas, Joni Mitchell, Captain Beefheart, Cat Stevens, the Carpenters, Gladys Knight and the Pips, Al Green, the Flying Burrito Brothers, Elton John, Lynyrd Skynyrd, Eric Clapton, Jimmy Buffett, the Eagles, Don Henley, Aerosmith, Steely Dan, Iggy Pop, Rufus and Chaka Khan, Barry White, Patti LaBelle, Yoko Ono, Tom Petty and the Heartbreakers, the Police, Sting, George Strait, Steve Earle, R.E.M., Janet Jackson, Eric B. and Rakim, New Edition, Bobby Brown, Guns N’ Roses, Queen Latifah, Mary J. Blige, Sonic Youth, No Doubt, Nine Inch Nails, Snoop Dogg, Nirvana, Soundgarden, Hole, Beck, Sheryl Crow, Tupac Shakur, Eminem, 50 Cent and the Roots.

Then there are masters for largely forgotten artists that were stored in the vault: tens of thousands of gospel, blues, jazz, country, soul, disco, pop, easy listening, classical, comedy and spoken-word records that may now exist only as written entries in discographies.

Today Universal Music Group is a Goliath, by far the world’s biggest record company, with soaring revenues bolstered by a boom in streaming music and a market share nearly double that of its closest competitor, Sony Music Entertainment. Last year, Vivendi announced a plan to sell up to 50 percent of UMG. The sale is the talk of the music business; rumored potential buyers include Apple, Amazon and the Chinese conglomerate Alibaba. The price tag is expected to be hefty: In January, Deutsche Bank raised its valuation of UMG to more than $33 billion.

The label’s dominance rests in large part on its roster of current chart toppers — stars like Drake, Taylor Swift and Ariana Grande. But UMG’s reputation is also based on the great swaths of music history it owns, a canon that includes Frank Sinatra, the Beatles, Queen and many more artists and labels whose catalogs came under the UMG umbrella during decades of acquisition and consolidation. A key part of that legacy — the originals of some of the company’s most culturally significant assets — went up in smoke in 2008.

The vault fire was not, as UMG suggested, a minor mishap, a matter of a few tapes stuck in a musty warehouse. It was the biggest disaster in the history of the music business. UMG’s internal assessment of the event stands in contrast to its public statements. In a document prepared for a March 2009 “Vault Loss Meeting,” the company described the damage in apocalyptic terms. “The West Coast Vault perished, in its entirety,” the document read. “Lost in the fire was, undoubtedly, a huge musical heritage.”

The recordings that burned up in the Universal fire — like the songs that are blasting from car windows on the street outside your home, like all the records that you or I or anyone else has ever heard — represent a wonderment that we have come to take for granted. For most of human history, every word spoken, every song sung, was by definition ephemeral: Air vibrated and sound traveled in and out of earshot, never to be heard again. But technology gave humanity the means to catch sounds, to transform a soprano’s warble, a violin’s trill, Chuck Berry’s blaring guitar, into something permanent and repeatable, a sonic artifact to which listeners can return again and again.

The act of listening again has defined music culture for a century. It is also the basis of the multibillion-dollar record industry. Today a stupefying bounty of recordings is available on streaming audio services, floating free of the CDs, LPs and other delivery systems that once brought them to audiences. The metaphors we use to describe this mass of digitized sound bespeak our almost mystical sense that recorded music has dematerialized and slipped the bonds of earth. The Cloud. The Celestial Jukebox. Something close to the entire history of music hovers in the ether, waiting to be summoned into our earbuds by a tap on a touch-screen.

This is the utopian tale we tell ourselves, at least. In fact, vast gaps remain between the historical corpus of recorded music and that which has been digitized. Gerald Seligman, executive director of the National Recording Preservation Foundation, a nonprofit organization affiliated with the Library of Congress, estimated in 2013 that less than 18 percent of commercial music archives had been transferred and made available through streaming and download services. That figure underscores a misapprehension: the assumption that the physical relics of recorded sound are obsolete and expendable. “It feels as if music has evolved beyond the reach of objects,” says Andy Zax, a Grammy-nominated producer and writer who works on reissued recordings. “In fact we are as dependent on irritating physical stuff as we ever were.”

The objects in question are master recordings: millions of reels of magnetic tape, stored in libraries like the one that occupied the backlot vault. These archives hold other masters of various vintages: the lacquer, glass and metal masters that predated tape, and disk drives and digital tapes from the past few decades. They comprise, as Zax said at a music conference, “a bewildering array of formats: albums, singles, demos ... the entire careers of artists we know everything about and artists we know nothing about. ... The future of all of the recorded music that we have ever heard — and, for that matter, all of the recorded music that we haven’t heard yet — depends on our ability to maintain these artifacts.”

It is sonic fidelity, first and foremost, that defines the importance of masters. “A master is the truest capture of a piece of recorded music,” said Adam Block, the former president of Legacy Recordings, Sony Music Entertainment’s catalog arm. “Sonically, masters can be stunning in their capturing of an event in time. Every copy thereafter is a sonic step away.”

This is not an academic point. The recording industry is a business of copies; often as not, it’s a business of copies of copies of copies. A Spotify listener who clicks on a favorite old song may hear a file in a compressed audio format called Ogg Vorbis. That file was probably created by converting an MP3, which may have been ripped years earlier from a CD, which itself may have been created from a suboptimal “safety copy” of the LP master — or even from a dubbed duplicate of that dubbed duplicate. Audiophiles complain that the digital era, with its rampant copy-paste ethos and jumble of old and new formats, is an age of debased sound: lossy audio files created from nth-generation transfers; cheap vinyl reissues, marketed to analog-fetishists but pressed up from sludgy non-analog sources. “It’s the audio equivalent of the game of ‘Telephone,’ ” says Henry Sapoznik, a celebrated producer of historical compilation albums. “Who really would be satisfied with the sixth message in?”

The remedy is straightforward: You go back to the master. This is one reason that rereleases of classic albums are promoted as having been painstakingly remastered from the original tapes. It’s why consumers of new technologies, like CDs in the 1980s, are eager to hear familiar music properly recaptured for the format. Right now, sound-savvy consumers are taking the next leap forward into high-resolution audio, which can deliver streaming music of unprecedented depth and detail. But you can’t simply up-convert existing digital files to higher resolution. You have to return to the master and recapture it at a higher bit rate.

But the case for masters extends beyond arguments about bit depth and frequency ranges audible only to dogs. It enters the realms of aesthetics and phenomenology. Simply put, the master of a recording is that recording; it is the thing itself. The master contains the record’s details in their purest form: the grain of a singer’s voice, the timbres of instruments, the ambience of the studio. It holds the ineffable essence that can only truly be apprehended when you encounter a work of art up-close and unmediated, or as up-close and unmediated as the peculiar medium of recorded sound permits. “You don’t have to be Walter Benjamin to understand that there’s a big difference between a painting and a photograph of that painting,” Zax said in his conference speech. “It’s exactly the same with sound recordings.”

The comparison to paintings is instructive. With a painting, our task as cultural stewards is to hang the thing properly, to keep it away from direct sunlight, to guard it from thieves. A painting must be maintained and preserved, but only in rare cases will a technological intervention improve our ability to see the artwork. If you were to stand before the Mona Lisa in an uncrowded gallery, you would be taking in the painting under more or less ideal circumstances. You will not get a better view.

In the case of a recording, a better view is possible. With recourse to the master, a recording’s “picture” can, potentially, be improved; the record can snap into sharper focus, its sound and meaning shining through with new clarity and brilliance. The reason is a technological time lag: For years, what people were able to record was of greater quality than what they were able to play back. “Most people don’t realize that recording technology was decades more sophisticated than playback technology,” Sapoznik says. “Today, we can decode information off original recordings that was impossible to hear at any time before.”

The process of revisiting and decoding can transfigure the most familiar music. In May 2017, a new box set of the Beatles’ “Sgt. Pepper’s Lonely Hearts Club Band” was released to mark the album’s 50th anniversary. “Sgt. Pepper’s” is one of the most famous recordings in history, but the version most listeners know is the stereo mix, which was of secondary importance to the Beatles, their producer George Martin and his engineer, Geoff Emerick. It was the mono mix that consumed the Beatles’ attention, and it is to those materials that the box set’s producer, Martin’s son Giles, returned, creating a fresh stereo mix from the mono masters. “The job was to strip back layers, to get back to that original sound and intent,” he says. “The detail we can garner from the mix compared to what they could have done 50 years ago is fantastic.”

The result is a vivid new “Sgt. Pepper’s.” In certain quarters, the album has been regarded as twee, but Giles Martin’s mix reveals a burlier rock ’n’ roll record. The box set opens new vistas on the album’s themes and adds force to its pathos. The opus “A Day in the Life” sounds more ominous than ever, a portent of late ’60s chaos, of the storm gathering on the other side of the Summer of Love. These epiphanies would not have been possible without masters. “Working without the master tapes,” Martin says, “would be like a chef having to use precooked food.”

The “Sgt. Pepper’s” masters are kept in a secure location in London. The tape boxes are marked with recording notes that helped guide Martin’s mixing decisions. The tapes themselves feature additional recordings — alternate versions, overdubs, studio chatter — that were included on the rerelease. Tens of millions of copies of “Sgt. Pepper’s” have been sold over the years; it may seem precious to place special value on the original of a record that is so well known and ubiquitous. But the masters in the London archive are unique. They have greater fidelity than any copy of “Sgt. Pepper’s” that is out in the world. They have more documentation than any version anywhere. And the masters contain more Beatles music too.

The same is surely true of many masters destroyed in the Universal fire. John Coltrane and Patsy Cline music has not vanished from the earth; right now you can use a streaming service to listen to Coltrane and Cline records whose masters burned on the backlot. But those masters still represent an irretrievable loss. When the tapes disappeared, so did the possibility of sonic revelations that could come from access to the original recordings. Information that was logged on or in the tape boxes is gone. And so are any extra recordings those masters may have contained — music that may not have been heard by anyone since it was put on tape.

There is another defining characteristic of masters — the “Sgt. Pepper’s” tapes, the tapes stacked on the shelves of Building 6197 and countless other masters as well. They are corporate assets. In 2019, most commercial recordings from the past century-plus are controlled by three gigantic record companies: UMG, Sony and Warner Music Group. These “big three” labels get to exploit this material for profit. But they are also the warehousers of millions of cumbersome master recordings. They’re in the storage business.

That task is expensive and complex, and if the past is an indication, it may be a job for which record companies are ill suited. The Universal fire brought losses on an unprecedented scale, but it was only the most recent disaster to strike the masters holdings of American record labels. These disasters include not only events like fires but also instances of neglect and even willful destruction by the labels themselves, a hair-raising history that reaches back to the beginnings of the music business.

Today industry professionals familiar with archiving practices question the big three labels’ commitment to preservation. (A number of these insiders, including individuals with knowledge of the backlot fire, spoke on condition of anonymity, concerned they could face professional consequences with UMG and other labels.) One audio specialist said: “Labels need to see payoff: ‘We have a release next year from this artist.’ But as far as, ‘We have this inventory on the shelves, let’s preserve it’ — that’s not the attitude. An old recording that’s deteriorating on the shelf is not causing alarm.”

The result is a crisis, a slow-motion assault on our musical heritage that is poorly understood by many within the record industry, to say nothing of the public at large. Had a loss of comparable magnitude to the Universal fire occurred at a different cultural institution — say, the Metropolitan Museum of Art — there might have been wider awareness of the event, perhaps some form of accountability. Yet the conservation mission faced by record labels may be no less vital than those of museums and libraries. Recorded music is arguably America’s great artistic patrimony, our supreme gift to world culture. How should it be safeguarded? And by whom?

I met Randy Aronson for the first time on a spring day in 2016. He was living in the same three-bedroom house where he had been jolted awake by a phone call on the morning of the fire. It was a small house, and it was a full one, occupied by Aronson and his wife, one of their two adult daughters, the daughter’s boyfriend, three dogs and a cat.

As a young man, Aronson did some acting, and he recently returned to the stage, starring in a community-theater comedy about the 1930s golden age of radio. Aronson has the look of a guy who can do a good screwball turn. He is tall and husky, with an elastic face and eyes that hold a gleam. When I arrived at his house, he led me into the living room, where I noticed a BB gun. “There are coyotes around here,” he said. “I don’t shoot at them — I shoot around them.” Aronson was adopted as an infant. His father worked as a repairman for the Otis Elevator Company for 35 years. “That’s where I got my loyalty to one company,” Aronson said. “I know that sounds funny, under the circumstances.”

In January 2016, Aronson lost his job at UMG. He had continued to direct the company’s vault operations following the fire, overseeing approximately 1.5 million master tapes that UMG maintained in storage facilities around the United States. He said he was never given a reason for his dismissal but chalks it up to differences of “archiving philosophy.” “I wasn’t speaking their language,” he said.

I sought out Aronson more than a year after learning about the vault fire. His account of events and knowledge of the vault’s contents confirmed the picture that had emerged from my review of legal documents and UMG’s internal records. Aronson admits he would not have consented to interviews were he still with UMG. But he insists he is not motivated by animus toward the company. He agreed to talk, he said, because he hopes the story of the fire will lead to a broader conversation about preservation. He expressed anxiety about his job prospects in light of his participation in this article. “I am a man of strong convictions on what I think is proper storage and preservation standards of music tape,” he wrote in an email in 2016. “I am also a 58-year-old man who is seeking employment with one of the few remaining music companies.”

There’s no mistaking Aronson’s strong convictions, and strong emotions, about the Universal fire. In dozens of conversations and email exchanges, he described the event as a personal trauma. “Sometimes I forget that there was life before the fire,” he said. “Even now, it gets me choked up, thinking about all those tapes.”

The fate of all those tapes has been an open secret for years. It hides in plain sight on the internet, popping up on message boards frequented by record collectors and audio engineers. In a 2014 interview, Richard Carpenter, one-half of the superstar 1970s duo the Carpenters, stated that masters for the group’s multimillion-selling A&M albums were lost on the backlot. “A lot of those masters ... they went up in the fire at Universal,” Carpenter said. References to the loss of Decca and Chess masters in the fire appeared more than three years ago in the Wikipedia entry for Universal Studios Hollywood and were still on the page at the time of this writing.

Yet the news has never reached the broader public. In part, this represents a triumph of crisis management. In the days following the fire, officials at UMG’s global headquarters in Santa Monica, Calif., and in New York scrambled to spin and contain press coverage.

In an email sent to UMG executives and P.R. staff members on June 3, 2008, Peter LoFrumento, the company’s spokesman, reported on efforts to downplay the story, attaching articles from The New York Times, The New York Daily News and The Los Angeles Times that reflected UMG’s account of events. The officials copied on the email included Zach Horowitz, UMG’s president and chief operating officer. Horowitz, who has since left the company, declined to comment for this article.

“We stuck to the script about physical backups and digital copies,” LoFrumento wrote in the email. The company, he claimed, had steered Jon Healey, a Los Angeles Times writer, toward a more favorable view: “We were able to turn Healey around on his L.A. Times editorial so it’s not a reprimand on what we didn’t do, but more of a pat on the back for what we did.” That editorial, published in the paper’s June 3 edition, offered comforting news: “At this point, it appears that the fire consumed no irreplaceable master recordings, just copies.”

Other newspaper accounts described damage to master recordings by little-known artists, whose names may have been cherry-picked by UMG in an effort to downplay the gravity of the loss. A New York Times article on June 3 cited recordings by “pop singers Lenny Dee and Georgie Shaw” as examples of the “small number of tapes and other material by ‘obscure artists from the 1940s and ’50s’ ” that were affected by the fire. The Times ascribed these assertions to a UMG spokesman. The Daily News article also invoked the loss of “original recordings from organ virtuoso Lenny Dee and 1950s hitmaker Georgie Shaw.” A possible explanation for the highlighting of Dee and Shaw comes from Aronson: He says that a UMG executive asked him, the day after the fire, for the names of “two artists nobody would recognize,” to be furnished to journalists seeking information on lost recordings.

That same June 3 Daily News article included a direct quotation from LoFrumento: “In one sense it was a loss. In another, we were covered,” he said. “It had already been digitized, so the music will still be around for many years.” The claim about digital backups, which was reported by other news outlets, also seems to have been misleading. It is true that UMG’s vault-operations department had begun a digitization initiative, known as the Preservation Project, in late 2004. But company documents, and testimony given by UMG officials in legal proceedings, make clear that the project was modest; records show that at the time of the fire approximately 12,000 tapes, mostly analog multitracks visibly at risk of deterioration, had been transferred to digital storage formats. All of those originals and digital copies were stored in a separate facility in Pennsylvania; they were not the items at issue in the fire. The company’s sweeping assurance that “the music” had been digitized appears to have been pure spin. “The company knew that there would be shock and outrage if people found out the real story,” Aronson says. “They did an outstanding job of keeping it quiet. It’s a secret I’m ashamed to have been a part of.”

Doug Morris, UMG’s chairman and chief executive at the time of the fire, declined to comment for this article; he left the company in 2010. In a statement provided to The New York Times last month, a current UMG spokesman said that the company was unable to comment on the 2008 fire. “In this case, there are constraints preventing us from publicly addressing some of the details of the fire that occurred at NBCUniversal Studios’ facility more than a decade ago,” the statement read. “However, in the intervening years, UMG has made significant investments — in technology, infrastructure and by employing the industry’s foremost experts — in order to best preserve and protect these musical assets and to accelerate the digitization and subsequent public availability of catalog recordings.”

Back in 2008, UMG undoubtedly feared the public embarrassment that news of the losses could bring. But Aronson and others suggest that UMG was especially concerned about repercussions with the artists, and the estates of artists, whose recordings were destroyed.

Record contracts are notoriously slanted in the favor of labels, which benefit disproportionately from sales and, in most cases, hold ownership of masters. For decades, standard artists’ contracts stipulated that recordings were “work for hire,” with record companies retaining control of masters in perpetuity. It is a paradox of the record business: Labels have often been cavalier about physically safeguarding masters, but they are zealous guardians of their ownership and intellectual-property rights.

Certain musicians, usually big stars, negotiate ownership of masters. (“If you don’t own your masters, your master owns you,” quipped Prince in 1996, at the height of a high-profile standoff with Warner Brothers.) It is unclear how many of the artists whose work was lost in the Universal vault had ownership of their physical masters, or were seeking it. But by definition, artists have a stake in the intellectual property contained on those masters, and many artists surely expected UMG to safeguard the material for potential later use. Had word of the fire’s toll emerged, many of the biggest names in pop music, and many profitable artist estates, would have learned that UMG had lost core documents their catalogs rest on — a source for everything from potentially lucrative reissues to historical preservation to posthumous releases. That scenario could have exposed UMG to a storm of questions, threats and reputational damage from across the industry.

But in the decade since the fire, UMG has faced little apparent blowback from artists or their representatives. It is probable that musicians whose masters were destroyed have no idea that a vault holding UMG masters had burned down. (A UMG spokesperson, asked if there has been any systematic effort to inform artists of the losses, said the company “doesn’t publicly discuss our private conversations with artists and estates.”)

The closest UMG came to a public imbroglio may have been in 2010, when, Aronson says, he was sent on an unusual business trip to Pennsylvania. He had been told by a UMG executive that one of the most powerful men in the music industry, Irving Azoff, was asking questions about the loss of Steely Dan masters in the fire. Azoff, the former chairman of MCA Inc., is now the chairman and chief executive of Azoff MSG Entertainment, a live entertainment conglomerate, as well as the “supermanager” chairman of Full Stop Management, whose roster of clients includes Steely Dan and the Eagles. A quarrel with Azoff was an unwelcome prospect. Luckily, the tapes he was concerned about, multitrack masters of Steely Dan’s first releases, turned out to have been moved to UMG’s Pennsylvania tape vault before the fire.

Azoff sent Elliot Scheiner, a celebrated record producer and mixer who had worked with Steely Dan, to confirm the tapes were intact. Aronson accompanied Scheiner to the Pennsylvania facility, the tapes were pulled, the matter was dropped. (Asked about this incident, both Azoff and Scheiner declined to comment.) In fact, UMG documents suggest that Steely Dan masters — different tapes than those sought by Azoff — were in Building 6197 when the fire hit. According to Aronson, these likely included certain album masters, as well as multitrack masters holding outtakes and unreleased material. “Those songs,” Aronson says, “will never be heard again.”

UMG avoided bad publicity, but in the months after the fire, the feelings of shock and chagrin remained acute for Aronson and his vault operations colleagues. As for senior executives, it is unclear how engaged they were in the questions debated, and the decisions made, in the fire’s aftermath. “I got the sense they felt the less top executives knew, the less accountable they’d be,” Aronson says. “I felt I was being shielded from top execs and carted in for insurance and legal meetings.”

There were many such meetings. In December 2009, UMG filed a lawsuit against NBCUniversal, its former landlord at the vault, seeking compensatory damages for losses suffered in the fire. (Much of what we know about the event comes from depositions and documents that emerged from this litigation.) The suit claimed that NBCUniversal, which leased the backlot vault to UMG, “breached their duty of care,” resulting in the destruction of the warehouse and its contents. Legal wrangling ensued for more than three years, until February 2013, when UMG dropped the suit and the parties settled for an undisclosed sum. (Spokespeople for UMG and NBCUniversal declined to comment.)

The position staked out by UMG in the lawsuit was the opposite of that in its public statements. Rather than minimizing the fire’s impact, the company sought to prove the gravity of the event and the loss incurred. Aronson’s knowledge of the fire’s toll made him valuable to that cause. He was deposed multiple times and asked by UMG lawyers to submit declarations to the court on four occasions. “Although it was never said to me, I was certain that they loved my candor for legal reasons,” Aronson says. “I was the perfect counter to news releases that said the whole thing was a minor event.”