Via Chad Ford's Twitter:
"Xavier Henry not playing in Summer League b/c of contract dispute. How, given rookie salary scale?"
"Team customarily give player 120% of salary scale. Grizzlies owner Michael Heisley offered less. Thus ... no Henry in summer league"
"Note on Grizzlies: Teams can pay anything from 80% to 120% of rookie scale amount. In 95% of cases, teams pay the 120% amount"