Legal Question in Landlord & Tenant Law in California

You have no contract with the other roommates or the landlord. It appears that the third roommate, with the first two, has this "privity of contract". Your action would be solely against the person to whom you gave the deposit as it is that person who has the legal obligation to the landlord. You should have had him taken off the lease when you moved in so you could be substituted. In that case you would have had a valid contract with the landlord. That would not necessarily mean you would get your deposit back. Retaining deposits is a serious civil liability against landlords who do so without cause. But, by the lease, they have clearly spelled out reasons for giving the deposit back...usually at the end of a lease. Regardless of who is on the lease at this point, the landlord would have no obligation to return a deposit or part of one to anybody, if the lease was not terminating.