Network Security Liability
Third-party cyber coverage for claims alleging the insured's network security failure caused damage to others.
What It Is
Network security liability is a third-party insuring agreement within a cyber policy that covers defense costs and damages arising from claims that the insured's failure to prevent a security event caused harm to third parties. Covered security events typically include unauthorized access to or use of the insured's network, transmission of malware from the insured's systems to third parties, denial-of-service attacks originating from or facilitated by the insured's network, and unauthorized disclosure of third-party data in the insured's care.
This coverage is the cyber equivalent of a general liability policy's bodily injury and property damage coverage but focused on digital harms. It typically covers defense costs, settlements, and judgments. Most policies provide duty-to-defend coverage, meaning the carrier selects and pays for defense counsel, though some provide indemnity-only coverage where the insured selects counsel and seeks reimbursement.
Network security liability claims are growing as businesses in supply chains increasingly sue upstream vendors for security failures that cascade through connected systems. Contracts between businesses now routinely require minimum levels of network security liability coverage, similar to how contracts require general liability minimums.
Why It Matters for Brokers
For brokers, network security liability is the coverage most often required by client contracts, especially for technology, professional services, and healthcare accounts. Brokers must verify that the coverage meets contractual requirements for limits, retroactive dates, and definition of covered security events. Failure to secure adequate network security liability coverage can disqualify clients from contracts worth millions in revenue.
Real-World Example
A managed IT service provider's compromised credentials allow attackers to deploy ransomware across 14 client networks. Three clients sue the MSP for $4.2M in combined damages including business interruption, data restoration, and breach costs. The MSP's cyber policy's network security liability coverage with a $5M limit covers $3.8M in settlements plus $620,000 in defense costs, totaling $4.42M against the limit.
Common Mistakes
- 1Failing to verify that the policy's definition of security event matches the security obligations in the client's customer contracts.
- 2Not checking whether the policy covers transmission of malware, which is increasingly excluded or sublimited in some forms.
How brokerageaudit.com Handles This
brokerageaudit.com's Policy Checker extracts network security liability terms and compares them against uploaded client contracts to identify where coverage falls short of contractual requirements. The COI Manager tracks certificate requests that specify cyber liability requirements and flags when the placed coverage does not match.