The bill is sponsored by the California Apartment Association, which has long been at odds with the AIDS Healthcare Foundation over efforts to enact stricter rent control laws through ballot measures.

The AIDS Healthcare Foundation, which makes $2 billion a year in revenue, mostly from a chain of pharmacies and clinics, has faced criticism that its move into housing has strayed from its mission of helping people with HIV and AIDS.

In recent years, the Health Care Foundation has funded rent control efforts, spending more than $300 million to buy apartment complexes across the country, including in Skid Row neighborhoods, arguing they address chronic homelessness that other measures have failed to address.

The foundation says it has helped lift about 1,000 people off the streets and provided permanent housing for them in its Skid Row facilities, but the buildings suffer from heating, plumbing, elevator and electrical problems as well as pest infestations, according to an investigation published by The New York Times last fall.

Other supporters of Prop. 34 include health care groups such as the ALS Association and the California Chronic Care Coalition.