It goes without saying that the initial investment was a worthwhile move for Markkula: in 2018, Apple became the first company to achieve a valuation of $1 trillion (£760bn), and today it's worth almost $3.4 trillion (£2.6tn).

Markkula retired from Apple in 1996, and it’s unknown what percentage of company shares he still owns (if any). Today, he's estimated to have a fortune in the region of $1.2 billion (£913m) – not bad for someone who had to be tempted out of retirement!

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