The Mishnah in Talmud Bavli Megilah 23b mentions something called פורס על שמע.
Rash"i explains that the term פורס means "to divide". the idea, here, is that if there is a minyan of people who arrived in shul after the congregation has said the Shema, one person says Kaddish, Barchu and the 1st bracha of the Shema (Yotzer Hame'orot).
(FYI - Tosfot cites other sources regarding how many others are required for someone to do this action.)
Is this action done by anyone, currently? If not, approximately when and why was this abolished?
