When you own a building, it may make sense to buy a general liability insurance policy, so you don't lose the building in a lawsuit. If you're only renting a small space in a shared building, it may seem like you have little to no risk of injury lawsuits or other third-party challenges. But there are several reasons you may need to buy general liability insurance, regardless of how your business operates. Here are just a few of them. 
Your Lease May Require General Liability Insurance
Your lease may require you to purchase general liability insurance as a condition of using the space. After all, your landlord wants to make certain that you can take responsibility for your own actions within your own space. This frees them from a degree of liability against your own mistakes, and ensures that you will be a reliable tenant. Without proof of coverage, you won't even be able to get your lease approved, in some cases.
People Can Sue You for Things That Aren't Your Fault
Anyone can claim you're liable for their injury and try to sue you — even if it wasn't really your fault. For example, a client who was coming to visit you might slip and fall on a tile floor thanks to coffee spilled by a neighboring business owner. To the client, it's your building, so they might blame you and sue you. You may eventually get your neighbor to pay up, but you can save time and money on legal fees by letting your insurance company deal with it first. In addition, there's a chance that a judge could still rule that you're partially liable, and you might have to pay even though you don’t hold yourself at fault for the accident.
You Still Have Potential Liability
Even if you're in a shared office space and aren't responsible for maintenance, you can still have liability for injuries.
For example, you might leave something lying on the floor that someone trips on or an office chair that you bought might break when someone sits on it. One of your visitors or a contractor you hired might also cause property damage or commit a theft that you'd potentially be held responsible for as the person who invited them in. Finally, you might also want coverage for any accidental damage or injuries you cause when you go out to see a client at their location.