An Act improving the tax administrative laws of the Commonwealth

This bill amends Massachusetts tax laws to strengthen the state's ability to challenge transactions that lack a genuine business purpose beyond tax avoidance. It requires taxpayers to prove both a valid business reason and economic substance for such transactions, while explicitly protecting routine business decisions like choosing between debt and equity financing. Additionally, the legislation allows corporations to request a six-month extension for filing tax returns by paying an estimated amount in advance, and it mandates that the state pay reasonable attorney fees to taxpayers who win appeals against tax assessments. Finally, the bill clarifies the schedule for quarterly estimated tax payments, specifying that each of the four installments must equal 25 percent of the required annual payment.