> The 43-year-old’s remaining stake in the ride-hailing company now constitutes about a fifth of his $3 billion fortune, according to the Bloomberg Billionaires Index, down from about 75% before the lockup.
To be fair, if I had 75% of my net worth in a single asset, I'd also try to diversify. My wife and I both have lots of stock in the companies we work for, due to RSUs and employee stock purchase programs; and although we both believe our companies are a good investment overall, we regularly sell shares just so that we don't have so many of our eggs in those two baskets. 20% is a perfectly reasonable target I think.