No, even better would be to trigger a revaluation of all stock values on that date, and tax the income (as normal income, not capital gains) as if 100% of their stock was sold at that price.

So if you hold 100 million shares valued at 1 USD/share, and sell 1 million at 2 USD/share, your tax liability will be assumed on you selling 100 million shares at 2 USD/share (or 200 million of regular income).