Larry Ellison, the 74-year-old billionaire cofounder of Oracle, is one of the most interesting men in tech.

Whether yacht racing, buying whole Hawaiian islands, or trash-talking competitors, there's always a good chance we'll be surprised with what Ellison, who has a net worth of $68.4 billion, does next.

Here's how he went from two-time college dropout all the way to international playboy and tech titan.

Larry Ellison currently has a net worth of $68.4 billion, according to Forbes. That makes him the seventh-richest person in the world.

Larry Ellison
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Source: Forbes

Lawrence Joseph Ellison was born in the Bronx on August 17, 1944, the son of a single mother named Florence Spellman.

Larry Ellison, Oracle executive chairman of the board and chief technology officer, delivers a keynote address during the 2014 Oracle Open World conference on Sept. 28, 2014 in San Francisco, California.
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Source: Bloomberg

When he was 9 months old, baby Larry came down with pneumonia. His mom sent him to Chicago to live with his aunt and uncle, Lillian and Louis Ellison.

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Source: Bloomberg

Louis, his adoptive father, was a Russian immigrant who took the name "Ellison" in tribute to the place in which he entered the US: Ellis Island.

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Ellison went to high school in Chicago's middle-class South Side before attending the University of Illinois at Urbana-Champaign.

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Source: Bloomberg

When his adoptive mother died during his second year at college, Ellison dropped out. He tried college again later at the University of Chicago but dropped out again after only one semester.

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Source: Bloomberg

Finally, in 1966, a 22-year-old Ellison moved to Berkeley, California — near the future Silicon Valley, already the place where the burgeoning tech industry was taking off.

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Source: Inc.

He made the trip from Chicago to California in a flashy turquoise Thunderbird that he thought would make an impression in his new life.

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Ellison bounced around from job to job, including stints at companies like Wells Fargo and the mainframe manufacturer Amdahl. Along the way, he learned computer and programming skills.

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The turning point came when Ellison came to work for the electronics company Ampex, which had a contract to build a database for the CIA codenamed "Oracle."

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Source: Inc.

In 1977, Ellison and partners Bob Miner and Ed Oates founded a new company, Software Development Laboratories. The company started with $2,000 of funding, $1,200 of which came out of Ellison's own pocket.

Cofounders of Oracle.
Oracle

Source: Inc.

Ellison and company were inspired by IBM computer scientist Edgar F. Codd's theories for a so-called relational database — a way for computer systems to store and access information. Nowadays, they're taken for granted, but in the '70s, they were a revolutionary idea.

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The first version of the Oracle database was version 2 — there was no version 1. In 1979, the company renamed itself Relational Software Inc., and in 1982 it formally became Oracle Systems Corp., after its flagship product.

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Source: Inc.

As one of the key drivers of the growing computer industry, Oracle grew fast. In 1986, Oracle had its initial public offering, reporting revenue of $55 million.

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Source: Inc.

Still, in 1990, Oracle had to lay off 10% of its workforce, about 400 people, because of what Ellison later described as "an incredible business mistake." Oracle allowed its salespeople to book future sales in the current quarter, meaning all its numbers were skewed. It resulted in lawsuits and trouble with regulators.

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Source: CRN

It didn't get the decade off to a great start. After adjusting for that huge error, Oracle was said to be close to bankruptcy. At the same time, rivals like Sybase were eating away at Oracle's market share.

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Ellison is known for his willingness to trash-talk competitors. For much of the '90s, he and Oracle were locked in a public-relations battle with the competitor Informix, which went so far as to place a "Dinosaur Crossing" billboard outside Oracle's Silicon Valley offices at one point.

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Source: Fortune

But Oracle just kept steamrolling over the competition. And with Ellison as Oracle's major shareholder, his millions kept rolling in. He started to indulge in some expensive hobbies — including yacht racing. That's Ellison at the helm during a 1995 race.

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Source: Bloomberg

He also sponsors the Oracle USA sailing team, which won the America's Cup in 2010.

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Source: Bloomberg

Ellison even managed to turn a potential loss into a big win. In 1999, Ellison's protégé Marc Benioff left Oracle to work on a new startup called Salesforce.com. Ellison was an early investor, putting $2 million into his friend's new venture.

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When Benioff found out that Ellison had Oracle working on a direct competitor to Salesforce's product, he tried to force his mentor to quit the company's board. Instead, Ellison forced Benioff to fire him — meaning Ellison kept his shares in Salesforce.

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Given that Salesforce is now a $115 billion company, Ellison personally profits even when his competitors do well. It has led to a rocky relationship between the two executives that continues to this day, with the two taking shots at each other in the press.

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In fact, Salesforce aside, the dot-com boom of the late '90s benefited Oracle, too: All of those new dot-com companies needed databases, and Oracle was there to sell them.

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When Steve Jobs returned to Apple as CEO in 1997, he asked Ellison to sit on the board. Ellison stuck around for a while but felt that he couldn't devote the time.

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Source: Inc.

With the coffers overflowing, Ellison was able to lead Oracle through a spending spree once the dot-com boom was over and prices were low. In 2004, for example, Oracle snapped up the HR software provider PeopleSoft for $10.3 billion.

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Starting in the 2010s, Ellison started to take more of a back seat, handing more responsibilities to trusted lieutenants, like Mark Hurd and Safra Catz ...

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Source: Inc.

... but his spending didn't slow down. In 2012, he bought 98% of the Hawaiian island of Lanai.

Four Seasons Resorts Lana'i

Ellison founded a startup called Sensei that does hydroponic farming on Lanai in March 2016.

Sensei farm not pictured.
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Source: Forbes

Ellison also purchased Hawaiian budget airline Island Air in 2014, before selling a controlling interest in the airline two years later after it struggled financially.

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Ellison has also invested in educational platform maker Leapfrog Enterprises.

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Not all of Ellison's side-projects have worked out, though: He was an early investor in Theranos, the blood-testing startup that shut down in 2018 after founder Elizabeth Holmes was accused of fraud.

Theranos founder Elizabeth Holmes
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In addition to the island, Ellison owns the Astor Beechwood Mansion in Newport, Rhode Island (pictured below) ...

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Source: Bloomberg

... this home in Malibu, California...

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Source: Bloomberg

... and this home in Woodside, California. He has another home in Rancho Mirage, California.

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Source: Bloomberg

Ellison also owns the Indian Wells tennis tournament.

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Source: Bloomberg

Ellison's spending habits are so extreme that his accountant, Philip Simon, asked him to "budget and plan" in 2002, according to Bloomberg.

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Source: Bloomberg

Ellison has been married and divorced four times. Coupled with his extreme wealth, it's given him a reputation as an international, jet-setting playboy. He's said to be dating Nikita Kahn, a model and actress.

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Ellison has two children. His daughter Megan is an Oscar-nominated film producer, having worked on Zero Dark Thirty and American Hustle.

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Source: Forbes

Ellison's son David is also in the film business, producing films including 'The Terminator' and 'Mission: Impossible.'

Larry Ellison (left) and his son, David.
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Source: Forbes

In 2014, Ellison officially stepped down as Oracle CEO, handing control over to Hurd and Katz. At that time, Ellison held the title of fifth-richest person in the world.

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Source: Inc.

In 2016, Ellison scored a personal coup: Back in 1998, he had made a $125 million investment in ex-Oracle exec Evan Goldberg's startup business-management software firm, NetSuite ...

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Source: Bloomberg

... which ended up working out, when NetSuite CEO Zach Nelson negotiated the sale of the company to Oracle for $9.3 billion, netting Ellison a cool $3.5 billion in cash for this stake. NetSuite investor T. Rowe Price tried to block the deal, citing Ellison's conflict of interest, but it closed in November 2016.

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Source: Bloomberg

Oracle is slowly but surely transitioning its business to the cloud — giving Larry Ellison plenty of opportunities to take potshots at Amazon Web Services, the leading player in the cloud computing market.

Larry Ellison at Oracle OpenWorld '16.
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Source: Geekwire

Ellison has other gigs outside Oracle, too. He joined the board of directors at Tesla on December 28, 2018, where he's been a major investor. Earlier in 2018, Ellison described Tesla CEO Elon Musk as a "close friend," and defended him from critics.

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Ellison is also a noted philanthropist. In May 2016, Ellison donated $200 million to a cancer treatment center at the University of Southern California.

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Source: Forbes

In 2010, he signed The Giving Pledge pioneered by Bill Gates and Warren Buffett, pledging to donate 95% of his fortune before he dies.

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Source: Bloomberg

Beyond those gigs, Ellison is still actively engaged with Oracle. He serves as the company's chairman and chief technology officer.

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Source: Forbes

He might not be in the top spot, but he's still very much the face of the company, helping guide it through these choppy waters. And the rest, as they say, is history.

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