A Brownfield Redevelopment credit is authorized by MCL 208.1437. For tax years ending on or after April 8, 2008, if the credit allowed for the tax year exceeds the qualified taxpayer's tax liability for the tax year, the qualified taxpayer may elect to have the excess refunded at a rate equal to 85% of that portion of the credit that exceeds the tax liability of the qualified taxpayer for the tax year and forgo the remaining 15% of the credit and any carryforward.

For a qualified taxpayer that chooses the refundable option, the excess portion of this credit, less the 15% discount, is treated on the annual return as a payment. The credit calculation is reported on 2008 MBT Form 4584, the amount carries to Form 4574, and then to Form 4567, Line 42.

The refundable amount will be subject to offsets (e.g., other unpaid taxes) under the same rules as apply to any MBT tax refund. On the return the qualified taxpayer will identify how much of its total overpayment should be applied as a credit forward to the next tax year, and how much should be refunded. Of the total overpayment, after offsets, the portion for which the qualified taxpayer requests a refund will be refunded fully and promptly. If the refund is not made within 45 days, the standard rules under which the State must pay interest will apply. For the numerical example in the question, assuming no offsets, 85% of the $900,000 excess credit, or $765,000, would be available as a refund and/or credit forward.

Two additional items should be noted. First, the reference to "qualified taxpayer" indicates that an assignee does not have this election. Second, there is a type of Brownfield credit (see MCL 208.1437(4)) ranging from $10 to $30 million, in which 10% of the total credit is allowed each year for ten years. The statute granting the 85% refund option includes the phrase "if the credit allowed under this section for the tax year exceeds the qualified taxpayer's tax liability" (emphasis added). If a $20 million credit is approved under §1437(4), the credit allowed "for the tax year" will be $2 million each year. This refund option will not allow 85% of the entire $20 million to be refunded in a single year.