This nmeeds a lot of work- it's not my are of knowledge, but I'll try to get it started.
The MP 135/2003 was amended by federal government following allegations of meeting the old wishes of the business sector, it also anticipates the effect of the Tributary Reform. (The term exists, but I don't know what it means)
Notably it changed the means of verifying the COFINS amount to be receives by businesses.
The transformation of CONFINS to a non-accumulative tribute was one of the most important changes.
The rate raised from 3% to 7,6% in order to balance\match (?)the accumulative with the non-accumulative.
However, this resulted in adding a 153% tributary rate to this tribute.
Critics were generated by businessmen from the service sector mainly. Since they donít use raw materials, they may not reduce the tax value of receipts,
any value to credit title. (I'm afraid I can't work this phrase out)