(Testing the admins` patience a little further
)
The Massorites were a group of Jewish scholars who copied and handed down the text of the Hebrew Scriptures. However, they themselves did not make the alterations to the text, rather they merely passed on what had been handed down to them by the Sopherim (Soph-ehr-eem Scribes). E. W. Bullinger, in Appendix #30, p. 31, of The Companion Bible, makes the following observation about the relationship between the Sopherim and the Massorites.
"The Text itself had been fixed before the Massorites were put in charge of it. This had been the work of the Sopherim (from saphar, to count, or number). Their work, under Ezra and Nehemiah, was to set the Text in order after the return from Babylon; and we read of it in Neh. 8.8 (cp. Ezra 7.6,11). The men of ”the Great Synagogue’ completed the work. This work lasted about 110 years, from Nehemiah to Simon the first, 410-300 B.C.
"The Sopherim were the authorized revisers of the Sacred Text; and, their work being completed, the Massorites were the authorized custodians of it. Their work was to preserve it. The Massorah is called ”A Fence to the Scriptures,’ because it locked all words and letters in their places. ..."
from
http://www.geocities.com/Hebrew_Roots/html/hr-2-3-02.html
Most sites I`ve visited tend to date the Emendations to post-Ezra.