Zynga’s shares shot up as much as 20 percent in trading today, a day after Facebook revealed 12 percent of its revenue comes from the social gaming maker.

Facebook gets a huge chunk of its revenue from advertisements purchased by Zynga and from transaction fees on Zynga’s virtual goods. Zynga’s games also generate more pages where Facebook can place advertisements.

Zynga’s shares are trading as high as they ever have right now. Zynga is up around 14% right now and is trading at around $12 — higher than its debut of $11 when it first went public.

Source: SAI