Citing the need to respect the parliamentary calendar, Pietro Grasso said he could not examine “an abnormal number of amendments, without (setting) a precedent that would allow parliamentary proceedings to be blocked indefinitely.”
“For this reason…I consider the amendments not so much as unacceptable as inadmissible (from a legal point of view),” said Grasso, who has the last word on the matter.
The software used by Northern League senator Roberto Calderoli to draft 82,730,460 amendments to the bill generates endless variations of sentences by changing punctuation or individual letters.
He later withdrew around 10 million of the proposed changes, but that still left far more than parliament could feasibly examine.
The reform, aimed at easing Italy's notorious political gridlock, would replace the Senate with a much less influential second chamber of regional representatives.
Grasso's decision was a victory for Prime Minister Matteo Renzi, who aims to have the legislation – one of the signature reforms of his mandate – adopted by October 13th.
The bill, which is being examined by the Senate for a third time, has faced stiff resistance, including from within Renzi's own Democratic Party.
Italian media said the prime minister appeared, however, to have reached a deal with the party's rebellious left wing that would see it back the legislation when put to a vote again in the Senate.
From there it will return to the lower house of parliament before being put to a referendum, expected sometime in 2016.