SB 826, passed last year, added a section to the California Corporations Code to mandate that all corporations must include at least one female on their boards of directors. Larger corporations must include more than one. The benefit to corporations is unclear. The benefit to the state of California is even less clear.
Note that they do not need to include any males. A board of directors which is 100% female would be perfectly okay with the California Legislature, just not one which is 100% male. This is, somehow, not discriminatory.