If two INDIVIDUALS own a property, must both owners sign to commence an unlawful detainer action?
There is no such rule. Co-owners are considered agents of each other.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts...
No. Multiple owners do not require multiple signatures
A proper response would require a much more thorough and complete investigation into the history and facts set forth in your question. Any statements provided by me regarding your inquiry is nothing more than an opinion, and does not represent legal advice or create a client relationship.
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