Get your taxes done using TurboTax

The company has the box blank because they don't know the basis. The IRS requires the investor to keep up with the basis. The basis equals what you paid plus expenses to purchase and sell. The IRS says if you don't know the basis, enter zero so that you are taxed on the full amount.

Whoever told you to not declare income on your tax return is nuts. You have a legal tax form and it does go on your return.

I want to urge you to create a financial notebook that is kept separate from your tax return. Keep it safe and each year, add your year-end statements from all your financial accounts plus a copy of your W2’s, your  carryover information, and proof of your basis in your various investments. You must keep tax records  from the time you purchase until sold/ loss used plus 3 years. It is very easy to lose track of disallowed losses / carryforwards/ basis.

You can also use a spreadsheet. The IRS released this example relating to virtual currency but same premise for any investment, you have to know what you paid and when: