New California rental laws take affect January 1st, 2020. Assembly Bill 1482 imposes state wide rent control which limits how much rent can be raised each year for qualifying rental units. Rent increases are limited to 5% plus the Consumer Price Index ("inflation") for the region, capped at 10%.
The law backdates to the rent amount on March 15, 2019, so if a landlord has raised rent by more than the allowable increase since March, they will need to lower the rent on January 1st. Use this calculator to determine allowable rent increases.