Being part of the billionaires' club doesn't mean you have to be friends with your fellow members...
From the proposed cage fight between business rivals Elon Musk and Mark Zuckerberg to the spat between super-rich celebrities Kim Kardashian and Taylor Swift, which recently inspired a thinly veiled "diss track", grab your popcorn and read on for 10 of the most jaw-dropping billionaire feuds of all time.
All dollar amounts in US dollars.
Starting with a bang, the beef between these tech titans kicked off in 2016 when a rocket from Musk's SpaceX company that was carrying Zuckerberg's $200 million (£158m) internet satellite exploded during a pre-launch test.
Needless to say, the Facebook boss was incensed and took to the social media platform to express how "deeply disappointed" he was "that SpaceX's launch failure destroyed our satellite". According to Ars Technica, Musk and his team at SpaceX didn't take kindly to the rebuke.
In 2017, the pair once again clashed, this time over AI. Zuckerberg slammed Musk's warnings about the technology, calling the "naysayers" who "try to drum up these doomsday scenarios... really negative... and pretty irresponsible". Musk responded with a withering comeback, calling out Zuckerberg's "limited" understanding of the subject.
The feud intensified the following year amid the Cambridge Analytica scandal. Lambasting Zuckerberg's firm for its privacy issues, Musk made a show of deleting the SpaceX and Tesla Facebook pages, and went on to criticise everything from Facebook's perceived role in the 2021 US Capitol attack to Zuckerberg's stranglehold on Meta.
The feud really intensified last year following Musk's chaotic takeover of Twitter. Meta immediately started working on a copycat to appeal to disillusioned users, infuriating Musk.
Tensions came to a head in June when the "Chief Twit" challenged Zuckerberg to a cage fight, which he duly accepted. The pair were said to be "dead serious" about going through with the bout and the Italian government has even offered up Rome's Colosseum for the showdown. However, plans for the bout appear to have fallen by the wayside.
The superstar employee who could do no wrong, Marc Benioff wowed his boss Larry Ellison during a 13-year stint at Oracle that saw him become the software firm's youngest-ever vice president.
As well as being tight at work, the pair struck up a close friendship. According to Fortune, they holidayed on Ellison's yacht, spent Thanksgiving together, and even double-dated.
When Benioff left the company in 1999 to set up Salesforce, he had the full backing of Ellison, who went as far as to invest $2 million (£1.6m) in his protégé's new venture, and bag a seat on its board. But the relationship soon soured.
In 2000, Benioff discovered Oracle was secretly working on software that directly competed with Salesforce's products. None too pleased, he asked Ellison to resign from the board, but the Oracle founder refused and eventually had to be fired.
The conflict flared up at times throughout the 2000s and beyond, with Ellison mocking Salesforce as an "itty-bitty" application and the "roach motel of cloud computing". Benioff, meanwhile, took aim at Oracle for selling “false cloud” products.
In 2011, tensions came to a head when Ellison abruptly cancelled Benioff's speech at Oracle's OpenWorld conference after he made fun of Ellison and Oracle. Thankfully, the billionaires finally made amends in 2013 when they joined forces on a cloud project, putting their differences aside once and for all.
Rupert Murdoch and the late Silvio Berlusconi were as friendly as media moguls could be back in the 1990s, when Murdoch was in talks with the Italian tycoon turned prime minister to buy his Mediaset business empire.
While the deal was never completed, Murdoch eventually sweet-talked Berlusconi into buying his yacht the Morning Glory and – more importantly – letting Sky operate in Italy.
Sky Italia emerged in 2003 and swiftly dominated Italy's burgeoning pay TV market. The following year, Berlusconi's Mediaset entered the fray with its own pay TV venture and drew Murdoch's ire by attempting to block Sky Italia from securing the rights to broadcast Serie A football matches.
Now direct competitors, the relationship between the billionaires became increasingly acrimonious, and the fighting got more and more dirty.
In 2009, Murdoch accused Berlusconi of corruption by hiking Sky Italia's taxes to give his media empire an unfair advantage and launched lawsuits against two Mediaset firms. The Italian leader meanwhile railed against what he saw as a smear campaign waged against him by Murdoch's newspapers and TV channels, including Sky Italia, which ran ads attacking his government.
The furore died down after Berlusconi left office in 2011. Interestingly, Murdoch biographer Michael Wolff doubts there ever was a feud at all, putting the dispute down to "just business". According to the writer, Murdoch secretly had a lot of admiration for his Italian counterpart.
Russian oligarchs Roman Abramovich and Boris Berezovsky were thick as thieves during the 1990s when the pair were mopping up Soviet state assets on the cheap. Abramovich was Berezovsky's protégé, corporate partner and a close friend too.
Berezovsky helped fund the political party that propelled Vladimir Putin to power, but turned against the former KGB agent following his 2000 presidential win, becoming one of his harshest critics.
Berezovsky later claimed he was pressured by Putin loyalist Abramovich that same year into handing over his share of oil company Sibneft for the knockdown price of $1.3 billion (£1bn), well below its actual value. Berezovsky said he was given an ultimatum: sell up or have Putin confiscate the stake.
With the Russian president breathing down his neck, Berezovsky complied and fled Russia for the UK, where he was granted political asylum.
Berezovsky eventually had it out with his nemesis in 2011, when he sued Abramovich over their 2000 deal in the High Court, seeking unprecedented damages of over $4.8 billion (£3.8bn). But the biggest civil case in British legal history was ultimately dismissed, reportedly leaving Berezovsky a broken man.
In 2013, a year after he lost his legal battle, Berezovsky died in his Sunningdale mansion. The inquest into the suspicious death recorded an open verdict, with the coroner concluding that he couldn't be sure whether the oligarch, who'd previously been the target of two foiled assassination attempts, was the victim of foul play.
Wall Street investing legends Carl Icahn and Bill Ackman first crossed swords in 2003 when a "shmuck insurance" deal they hatched involving a company called Hallwood Realty went bad. The duo squabbled for years over the transaction and didn't settle the dispute until 2011. Following the settlement, tensions continued to simmer.
In 2013, the feud reached boiling point and then exploded – on live TV, no less.
The pair came to blows over the multilevel marketing company Herbalife. Ackman had labelled the firm a pyramid scheme and shorted its stock to the tune of a billion dollars, while Icahn, who wholeheartedly disagreed with Ackman, increased his holding.
Appearing together on CNBC's Fast Money Halftime Report, they entered into a shouting match, hurling insults and accusations at one another in an infamous incident that was dubbed the "Battle of the Billionaires".
Icahn called Ackman a "liar" and a "crybaby" with "one of the worst reputations on Wall Street". Ackman branded Icahn a bully "who takes advantage of little people". Incredibly, the bickering billionaires buried the hatchet the following year at the Delivering Alpha conference in New York, where they even managed an awkward hug.
But Ackman revived the feud in May last year, after the release of a damning report that alleged Icahn's eponymous investment firm had inflated assets and was run like a Ponzi scheme. Ackman launched an all-out attack on the company, comparing it to the ill-fated Archegos, a massively overleveraged hedge fund that imploded in 1998.
As well as duking it out with the current "Chief Twit", Mark Zuckerberg has traded barbs over the years with the microblogging platform's co-founder and former CEO Jack Dorsey. It wasn't always this way.
In 2011, Zuckerberg invited Dorsey to his home for a “memorable” dinner that consisted of a goat he'd hunted himself, which Dorsey later said was served cold. Whether Zuckerberg was trolling his rival is anyone's guess, but the pair did appear to have a cordial enough relationship.
That all changed in 2019. The duo clashed after Facebook opted against blocking false political ads in the interests of free speech.
Taking issue with this stance, Dorsey, who's passionate about stamping out misinformation, responded by announcing Twitter would no longer accept political ads and wouldn't be "compromised by money", a move that was seen as a not-so-veiled dig at the Facebook boss.
The following year, Zuckerberg called out Twitter for fact-checking Donald Trump's tweets, which resulted in another loaded comeback from Dorsey.
Since then, Dorsey has mocked Zuckerberg's Metaverse by reposting a tweet defining it as a "dystopian corporate dictatorship". More recently, he tweeted "All your Threads belong to us", a jibe at Meta's privacy policy and the social network the company launched in July last year, which many people have compared to Twitter (now X).
Back to Elon Musk, who has a penchant for getting into scraps with other billionaires. One of his most enduring feuds has been with Jeff Bezos, his arch-rival in the private space race.
The almost two-decades-long conflict began in 2004 when the pair met for dinner to discuss their reusable rocket plans. They failed to hit it off, with Musk later bemoaning that Bezos ignored much of the advice he offered.
The animosity sparked back into life in 2013 when Musk's SpaceX battled it out with Bezos' Blue Origin to obtain exclusive use of a NASA launchpad at Florida's Kennedy Space Center.
Bezos' firm filed a formal protest with the government to prevent SpaceX from taking over the facility, a move Musk decried as a "phony blocking tactic" to get one up on SpaceX and sabotage the company's goals. Musk's firm did, however, eventually secure the lease.
The pair later entered into a patent dispute and dissed each other's rockets and space travel plans. Then, in 2021, SpaceX beat Blue Origin in securing a $2.9 billion (£2.3bn) NASA contract to build a lunar lander. Blue Origin launched a legal bid to overturn the decision, which it ultimately lost, but landed an even fatter NASA contract to construct a more conventional lunar lander in May last year.
Throughout the feud, Musk has been the more outspoken of the two, going out of his way to rip Amazon Prime Video's Lord of the Rings series and gloat about surpassing Bezos as the world's richest person.
Though Elon Musk and Bill Gates have never been chummy, relations between the two tech tycoons became fraught in 2020 when they clashed over the pandemic.
Gates blasted Musk's dismissive attitude towards COVID-19 and the alleged misinformation he was spreading about the virus, calling his comments "outrageous". Musk responded by mocking Gates in a series of juvenile tweets, calling him a "knucklehead".
Gates then appeared to question Tesla's role in fighting climate change and shaded Musk by declaring he'd recently bought an electric Porsche Taycan, rather than a model from Tesla's range. Musk hit back, tweeting that the former Microsoft boss was "underwhelming" and had "no clue".
Gates offered an olive branch in 2021 when he praised Musk for his efforts fighting climate change, but couldn't resist adding the following year that his own contribution was significantly greater.
The pair also butted heads over cryptocurrency and space travel, with Gates criticising Musk's role in popularising environmentally harmful cryptos and saying he'd personally rather invest in vaccines than plan a trip to Mars. Gates also expressed apprehension over Musk's takeover of Twitter.
Meanwhile, Musk has accused Gates of shorting Tesla stock, posted childish memes mocking his weight, and recently recycled one of his Zuckerberg putdowns by calling Gates' knowledge of AI “limited” after the mega-philanthropist opposed his call to pause research into the tech. This is one billionaire feud that doesn't appear to be petering out anytime soon, that's for sure.
When the research organisation OpenAI was launched in 2015, co-founder Sam Altman expressed his admiration for Elon Musk, who was a major investor in the company. Altman envisioned OpenAI as a non-profit that could help prevent a dystopian future, an idea supported by Musk.
However, the billionaires' bromance came to a bitter end in 2018 when OpenAI launched a for-profit subsidiary, now valued at $80 billion (£63bn). The move led to tensions, prompting Musk to step down from the board and eventually file a lawsuit against Altman and other OpenAI executives, alleging that the company breached their funding agreement.
In response to the lawsuit, OpenAI accused Musk – who has since launched a rival AI company – of being motivated by "professional jealousy." In a blog post on its website, the company alleges that Musk initially supported the idea of turning OpenAI into a for-profit entity and sought to merge OpenAI with Tesla to assume the CEO position of both companies.
Since OpenAI released a statement, Musk has openly mocked the company and its co-founder on X (formerly Twitter). Musk shared a meme rebranding OpenAI as "ClosedAI" and posted a photo of Altman edited to show him holding up a company badge with “ClosedAI” on it, poking fun at the company’s decision to keep its technology secret.
As mentioned, last year Musk launched his own artificial intelligence company called xAI, complete with a chatbot to rival Altman's ChatGPT. Musk believed his chatbot, named Grok, had an edge over other AI bots on the market as it was programmed to respond to user prompts with a hint of humour.
However, Altman wasted no time in responding on social media, slamming Grok for its "cringey boomer humour." Yikes!
The feud between Swift and Kardashian began in 2016 when Kim's then-husband, Kanye West, released the song Famous. The controversial track contained explicit lyrics about Swift, which offended her. Following the backlash, West claimed that Taylor had given him permission to use the lyrics, a statement that Swift vehemently denied.
The situation escalated when Kardashian released edited footage of a private phone call between West and Swift discussing the song prior to its release. The audio clip sparked public debate over whether Swift had lied about not approving the lyrics.
When the illegally recorded phone call later leaked in full, it supported Swift's claim of a "frame job" orchestrated by Kardashian. West notably failed to mention the full scope of the lyrics during the call. However, the damage to Swift's "good girl" reputation was already done; she faced public ridicule and was branded a "snake."
The following year, Swift abandoned her all-American sweetheart image and released the album Reputation, which addressed the drama with West and Kardashian and the negative impact the feud had on her career through several songs, including Look What You Made Me Do.
In 2019, Kardashian claimed they'd "all moved on" from the feud during an interview on Watch What Happens Live. However, that same year, during an interview with Elle magazine, it seemed Swift still harboured Bad Blood.
"It would be nice if we could get an apology from people who bully us," Swift said, seemingly referencing the drama. "But maybe all I'll ever get is the satisfaction of knowing I could survive it and thrive in spite of it."
Seven years later, Swift once again referenced her spat with Kardashian during an interview with Time magazine. “Make no mistake—my career was taken away from me. You have a fully manufactured frame job in an illegally recorded phone call, which Kim Kardashian edited and then put out to say to everyone that I was a liar."
Swift added that the feud had a negative psychological impact on her and that she didn't leave the house for a year as a result of the public fallout.
The feud between Swift and Kardashian reached new heights this April with the release of Taylor's latest album, The Tortured Poets Department. Fans swiftly speculated that the song ThanK you aIMee was a Kardashian "diss track", noting that the uppercase letters in the title spell the name Kim.
The song references a woman named "Aimee" and includes lyrics about conflict, such as: "All that time you were throwing punches, I was building something, and I can’t forgive the way you made me feel."
This time around, it appears Kardashian is the one who has suffered damage to her reputation, as the star has lost 100,000 Instagram followers since the release of the song. However, a spokesperson for Kardashian claimed she was "over it" and wished for Swift to "move on."
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