Shareholders voted on the previously announced split at yesterday's annual meeting. Investors currently holding one share of Sun stock will receive one additional share in December.
Palo Alto-based Sun makes computer workstations and servers, and developed Java software.
Sun shares closed today at 114.75, up 1.56. Since plans for the share split were announced in September, the shares have gained 23 percent. In November 1998, Sun shares were trading at a 52-week low of about 29.