California Civil Code Section 1950.7 governs security deposits for commercial tenants. You can find the code here: http://law.onecle.com/california/civil/1950.7.html. According to 1950.7(c), a commercial landlord must return a tenant’s security deposit within 30 days after the landlord receives possession of the premises. Section 1950.7(f) goes on to provide a penalty for a landlord’s “bad faith” retention of a security deposit. This allows for a tenant to sue the landlord for an amount up to $200 plus actual damages. In order to get the $200 and prove damages, you’d have to sue the landlord and go to court. Another claim you could make would be for unfair business practices. However, please note that the only way to recover from the landlord is to sue them. You can do so in Small Claims Court without an attorney (in fact, attorneys are not permitted to appear in Small Claims court), though it may be wise to consult with one before taking legal action.
I hope this is helpful and I wish you good luck.
This response does not create an attorney-client relationship and is not intended to provide legal advice for your specific situation