Before July 4, 2012, the Higgs boson mass could only be in the 122 GeV to 130 GeV mass range (units where the proton mass is about 1 GeV, and the W and Z vector bosons are 80 GeV and 90 GeV, respectively).

FORBES: If I Want To Look Well-Read And In The Flow, What Do I Need To Know About The Higgs Boson Discovery And Announcement?

Refined data from the LHC collisions, released in March, put the range between 122.5 and 127.5 GeV.

WSJ: Physicists Find Signs of Higgs Boson, or 'God Particle'

The search for Higgs got its biggest boost in December when researchers at the Large Hadron Collider, or LHC, near Geneva, Switzerland, said that data from two independent experiments had narrowed the range of the would-be particle's likely mass to between 124 and 126 gigaelectronvolts, or GeV.

WSJ: Physicists Find Signs of Higgs Boson, or 'God Particle'