You can't always sell the share after exercise. You're taxed on the spread between strike price and fair market valuation as income on exercise, not on sale.
There is an exception around taxes for ISOs that recently became useful with the AMT change in the new tax law, but even in that case you often can't sell the share after you've exercised it without permission from your private company (which you are very unlikely to get).
There is an exception around taxes for ISOs that recently became useful with the AMT change in the new tax law, but even in that case you often can't sell the share after you've exercised it without permission from your private company (which you are very unlikely to get).