ISO and Amount Subject to AMT ?

I exercised ISO last month, our company is Not a public traded company yet so I do not know the real value of the stock.

I received a statement, main numbers are below:

Cost Basis -- $10,500

Taxable Compensation: $0.00

Amount Subject to AMT: $33,000

Do I need to add $33,000 while calculating AMT for the estimated tax? Does the company think the stock real value is much higher so they added $33,000 to the AMT?

Thanks,

Mac