I did and didn't find an answer.  Apparently Lacerte determines the MA tax differently than ProFx.  Ask 10 CPAs and get 10 different answers.  Some (including a regional firm partner) said zero %.  Some agreed with Lacerte's approach while others agreed with ProFx.  I'm assuming the are simply trusting their software.  MA will not comment.

I did find this basic guidance:

Sec. 1202 provides special treatment for the sale of “qualified small business stock” by noncorporate shareholders. Prior to the enactment of the Economic Development Reorganization Act, Massachusetts provided no such incentives. The act provides for Part C taxable income (generally, income from the sale of capital assets held for more than one year) to be taxed at 3% instead of 5.3% for investments that meet the following qualifications (MA Gen. Laws ch. 62, §4):

• The investment is in a corporation domiciled in Massachusetts;
• The corporation was incorporated on or after January 1, 2011;
• The corporation had assets of less than $50 million at the time of the investment; and
• The corporation complies with the active business requirement of Sec. 1202.

In addition, the investment must be made within five years from the date of incorporation and held for three years or more.

There is an important distinction between the federal and the Massachusetts provisions. While the federal reduction in the gain applies only to C corporations, the Massachusetts reduction in the tax rate also applies to S corporations.