The answer to your questions will be found, for the most part, in the written lease. You refer to a standard CA commercial lease. No such thing. There may be leases that are used by certain landlords, but commercial leases can be quite unique depending on the negotiations that went on between the parties at the making of them.
If there is enough money involved in this issue, you would be prudent to have a commercial landlord-tenant attorney look at the lease and give you your options.
Good luck to you.
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I agree with Mr. Pedersen, there is no "standard" commercial lease. That said, typically a commercial triple net lease will require the tenant to make necessary repairs. It sounds as though it should have been obvious to the subtenant that there was a problem. I would approach the original tenant and let the tenant know that their subtenant is causing a problem. Let the tenant handle it since the tenant remains responsible under the lease.
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My colleagues are correct in their assessment of this facts presented. As they mention, there is no such thing as a standard commercial lease. As described, the landlord should make its request to the tenant to handle the problem. It is the tenant's responsibility to address the concern with the sub-tenant. If that doesn't work, consider consulting with a local landlord tenant attorney for a review of the lease and guidance in how to proceed under your particular facts. Good luck.
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My colleagues are correct that the answer lies in the lease you signed with your tenant. Most triple net commercial leases require the tenant to be responsible for all non-structural repairs, such as repair to the toilet. If the cause was due to pipes leading to the toilet, it may be landlord's responsibility, as a structural repair. If it is tenant's responsibility, then you need to look to the terms of the lease to see the remedies that you can exercise against the tenant.
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