A judgment void for want of jurisdiction is no judgment at all.
JOANIE SURPOSA UY vs. JOSE NGO CHUA, G.R. No. 183965, September 18, 2009.
“x x x.
A judgment void for want of jurisdiction is no judgment at all. It cannot be the source of any right or the creator of any obligation. All acts performed pursuant to it and all claims emanating from it have no legal effect. Hence, it can never become final, and any writ of execution based on it is void. It may be said to be a lawless thing that can be treated as an outlaw and slain on sight, or ignored wherever and whenever it exhibits its head.
X x x.”