Inland marine classes are traditionally sorted into filed and non-filed. The words describe forms and rates, not claims or registration of the insured items.
Filed class: its policy forms and rates are submitted to the state insurance regulator, usually as standard bureau forms such as ISO or AAIS programs. Filed forms work best when a class has many similar exposures that can be rated uniformly, as with personal articles or signs.
Non-filed class: historically written on the insurer's own terms. Classes such as cargo, construction and electronic data processing risks were seen as too diverse or too quick to change for standard forms and rating plans. The reason is the nature of the exposure, not its size; many non-filed accounts involve very valuable property.
Advantages and disadvantages:
Filed: uniform wording, so competing quotes are easy to compare; but the wording is rigid, changes wait for bureau form revisions, and the underwriter has less discretion.
Non-filed: terms can be tailored to an unusual exposure; but wording differs by insurer, so policies are harder to compare and must be read closely.