Couple in California finds $10M worth of gold coins on their property. The IRS wants their "fair" share. Their claim is the money did not belong to the couple because they didn't know it was on their property. Therefore it is found money and therefore taxable. Plus, they don't tax the face value of the coins, they want "fair market" value. Now, in order to keep the coins, should they wish, they will need to come up with $4m just to maintain ownership.