On Friday, October 18, 2016, Oracle founder and chairman Larry Ellison announced that Mark Hurd had passed away at age 62. He had been ill and was forced take a leave of absence from his job as CEO of Oracle last month, a role he shared with CEO Safra Catz.

"Mark was my close and irreplaceable friend, and trusted colleague," Ellison wrote to the announcement posted on Hurd's personal website. "Mark leaves his beloved wife Paula, two wonderful daughters who were the joy of his life, and his much larger extended family here at Oracle who came to love him."

In 2016, Hurd invited Business Insider's chief tech correspondent, Julie Bort, to spend a day with him watching him work. Bort ran after him during one of his biggest days of the year, when he met with customers, analysts and gave keynote speeches at Oracle's annual, massive tech conference. We are republishing that article, unedited, in its entirety.

Oracle had $37 billion in revenue that year. It has since grown its top line to $39 billion.

With $37 billion in annual revenue, Oracle is one of the world's biggest tech companies. And every year, tens of thousands of customers, partners, industry analysts, and journalists descend upon San Francisco for the company's OpenWorld tech conference.

It is a pinnacle week for the company's top execs — its two famous CEOs, Safra Catz and Mark Hurd, and its even more famous founder, Larry Ellison, who stepped down from the CEO role in 2014 to become executive chairman and CTO, though he's still very much the leader of the executive triad.

Oracle invited me to spend a full day shadowing Hurd last week at OpenWorld as he met with customers, analysts, and others on the biggest day of the conference.

During the week, Hurd met with nearly 500 people either in one-on-one meetings or in small groups, answering their questions, solving problems, issuing reassurances, and explaining the company's plans and strategy — all at a surprisingly exhausting pace.

It was a rare close-up look at the hard work a CEO does to run global tech company., "