Why on earth would you want to let someone know that you had a big payout? It's none of anybody else's business how much money I have and if nobody knows you can walk downtown in peace, go to restaurants, hang out with your same friends, and still have lovely ski or yacht holidays in peace.

The Bay Area and Seattle have quite a few "unknown" billionares. For example if you had less than 5% of Microsoft when it IPOd you were not listed in the S-1, and if you hung on by the mid 90s you could have been worth 8-9 figures.