We analyze the masses of the negative paritySU(6)70‐plet baryons using the 1/Ncexpansion to order 1/Ncand to first order inSU(3) breaking. At this level of precision there are twenty predictions which include the well known Gell‐Mann Okubo and equal spacing relations together with four new relations involvingSU(3) breaking splittings in differentSU(3) multiplets. Although the breaking ofSU(6) symmetry occurs at zeroth order in 1/Nc, it turns out to be small. The dominant source of the breaking is the hyperfine interaction which is of order 1/Nc. The spin‐orbit interaction, of zeroth order in 1/Nc, is entirely fixed by the splitting between the singlet states &Lgr;(1405) and &Lgr;(1520), and the spin‐orbit puzzle is solved by the presence of other zeroth order operators involving flavor exchange. © 2003 American Institute of Physics