Since 2003 several states in the charmonium mass region were discovered. While in the conventional c c-bar spectrum some states are missing, the number of states observed up to now is larger than empty spaces in the c c-bar spectrum. This, together with other difficulties to explain observed states as a c c-bar mesons triggered discussions on a possible exotic interpretations. In this proceedings we present current experimental status from B-factories of the so called X, Y and Z states.
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