California Code, Probate Code - PROB § 13501

(a) Property passing to someone other than the surviving spouse under the decedent's will or by intestate succession.

(b) Property disposed of in trust under the decedent's will.

(c) Property in which the decedent's will limits the surviving spouse to a qualified ownership. For the purposes of this subdivision, a devise to the surviving spouse that is conditioned on the spouse surviving the decedent by a specified period of time is not a “qualified ownership” interest if the specified period of time has expired.