Legal Question in Securities Law in California

The first issue is whether the person living there qualifies as a tenant. The law distinguishes between tenants and boarders. A tenant would be someone having their own distinct quarters within your property, separate and distinct from the part you occupy, typically with their own key and implied privacy rights. A boarder usually would have his or her own bedroom, but would share some or most of the rest of the property.

The distinction, although not always clear, can be important, because a boarder has less protection from being required to leave.

A tenant has lease rights that survive a voluntary sale of the house, and a buyer would be subject to those rights - in effect, the buyer has acquired an income property and must wait for the lease to expire before being entitled to possession. The buyer is just a new landlord. At the end of the lease term, the buyer would have to use lawful eviction procedures if the tenant didn't depart voluntarily. However, you say your house was sold at auction, suggesting a foreclosure, and the foreclosing lender's lien rights are presumably senior to the rights of your co-occupant, whether boarder or tenant. In foreclosures, a bona fide tenant may have 90 days, but a boarder is not a bonafide tenant and doesn't qualify for protection under than new law.

On the other hand, a boarder can be asked to leave on reasonable notice, and what's reasonable can be pretty short. The boarder may have a breach of contract claim if asked to leave in violation of an agreement for a longer residency, but he/she has no right of possession such as a tenant would have under a lease, and if the boarder fails to vacate, he/she becomes a trespasser rather than a holdover tenant.