If a condition precedent requires the performance of an act wrong of itself, the instrument containing it is so far void, and the right cannot exist. If it requires the performance of an act not wrong of itself, but otherwise unlawful, the instrument takes effect and the condition is void.
Cal. Civ. Code § 709
Conditions of Ownership
Enacted 1872.
Official source: California Legislative Information. Reproduced from public-domain California statutes; confirm against the official source for the current text. Not legal advice.