Winter conditions generate a high volume of claims against commercial property owners, and outcomes turn on doctrine that varies sharply by state.

Natural accumulation rules. Some states impose no duty to remove natural accumulations of snow and ice, while others require reasonable measures within a reasonable time after a storm ends.

Unnatural accumulation — ice formed by defective drainage, downspouts discharging across a walkway, or piled snow melting and refreezing — is actionable in nearly every state.

Ongoing storm rules suspend the duty during an active storm in several jurisdictions, with the period beginning after it ends.

Contractor arrangements. Snow removal contracts should specify trigger depths, response times, scope including ice treatment, documentation of each service, insurance with additional insured status, and indemnity consistent with state anti-indemnity limits.

Records. Weather data, service tickets with times, inspection logs, and photographs. Most defensible cases rest on a documented service performed within the contracted response time.

Lease allocation between landlord and tenant, and whether common areas are the landlord’s responsibility, which is where the parties usually litigate after the injured person sues both.