As Required by Written Contract

'As required by written contract' is a conditional clause that limits when certain coverage protections activate. It means endorsements like additional insured status, primary and noncontributory coverage, or waiver of subrogation only apply when you have a signed contract with the third party that specifically requires those protections. Without that written contractual obligation, the endorsement may not provide the expected coverage.

If your policy includes the phrase 'as required by written contract,' then yes, you need a signed contract in place that requires additional insured status. This conditional language means the endorsement only activates when there's a written contractual obligation. Without a contract requiring it, the additional insured protection may not apply even if your policy has the endorsement.

Blanket additional insured means the endorsement automatically applies to categories of parties (such as clients, landlords, or general contractors) without scheduling each one individually by name. 'As required by written contract' is conditional language that can appear in both blanket and scheduled additional insured endorsements, requiring a signed contract for coverage to apply. Many blanket additional insured endorsements include the 'as required by written contract' language, so the two concepts often work together rather than being opposites.