12.5 Commercial Auto Endorsements

Common Commercial Auto Endorsements

The base Business Auto and Motor Carrier forms are tailored with endorsements (CA-series forms). Producers must know what each one does and recognize the ISO form numbers tested on the national exam:

Drive Other Car trap: DOC is designed for an individual the business covers who does not own a personal auto — it fills the gap a PAP would otherwise fill (liability, medical payments, UM, and physical damage for non-owned autos the executive drives personally).

Rating Endorsements and the Experience Modifier

Larger commercial auto risks may be experience rated: their past loss history adjusts the manual premium up or down through an experience modification factor (mod). A mod below 1.00 is a credit (better-than-average losses); a mod above 1.00 is a debit (worse-than-average losses).

Worked experience-mod example: A trucking fleet has a manual premium of $80,000 and an experience mod of 0.85. Modified premium = $80,000 × 0.85 = $68,000 — a $12,000 credit for good loss experience. If the same fleet had a string of large losses producing a mod of 1.20, the modified premium would be $80,000 × 1.20 = $96,000, a $16,000 surcharge.

The mod gives insureds a direct financial incentive to control losses, and producers use it to demonstrate the dollar value of fleet safety programs.

Composite Rating and Additional Insured Status

Fleets with many vehicles are often composite rated — a single rate is applied to an exposure base (such as gross receipts, mileage, or unit count) instead of rating each auto separately. This simplifies administration and automatically picks up additions and deletions during the term, with a year-end adjustment.

Worked composite example: A delivery company is composite rated at $3.50 per $1,000 of gross receipts. Estimated annual receipts are $9,000,000. Deposit premium = ($9,000,000 ÷ $1,000) × $3.50 = $31,500. If audited actual receipts reach $10,000,000, additional premium = (1,000 additional thousands) × $3.50 = $3,500 due at audit.

Additional insured trap: A Lessor — Additional Insured (CA 20 01) endorsement protects the leasing company for liability arising out of the leased auto and names it as loss payee for physical damage. It does not, however, cover the lessor's own independent negligence unrelated to the auto.

Drive-Other-Car and Individual-Named-Insured Endorsements

Because the Business Auto form insures an organization, an owner or executive driving a personal or borrowed auto may have a gap. The Drive Other Car (DOC) endorsement extends liability, Med Pay, and UM to named individuals while driving autos they do not own (a company executive in a rental on vacation). The Individual Named Insured endorsement broadens a sole-proprietor's commercial auto to provide personal-auto-style coverage for the individual and family. A stem about a company-titled vehicle whose owner has no personal auto policy points to these endorsements.

Hired Auto Physical Damage and Rental Reimbursement

The base form may not cover physical damage to hired/rented autos unless added. The Hired Auto Physical Damage endorsement insures rented vehicles for collision/comprehensive (often with a cost-of-hire rating basis), and Rental Reimbursement / Loss of Use pays for substitute transportation while a covered auto is repaired. Businesses that frequently rent vehicles add these to avoid signing rental-counter waivers.

Additional Insured, Waiver of Subrogation, and Primary-Noncontributory

Commercial contracts routinely require the business to name another party as an additional insured on its auto policy, to provide a waiver of subrogation, and to make its coverage primary and noncontributory. The corresponding endorsements (e.g., CA 20 48 designated insured) extend liability to the specified party for the named insured's use of covered autos. The exam tests that additional insured status extends the policy's liability coverage to a third party, while a waiver of subrogation gives up the insurer's right to recover from that party after a loss.

Pollution, Trailer Interchange, and Mobile Equipment

The Pollution Liability — Broadened Coverage for Covered Autos (CA 99 48) restores limited auto-pollution coverage otherwise restricted. Trailer Interchange covers trailers swapped under interchange agreements. Understanding that the base auto form excludes most pollution except fuel-system upset, and that an endorsement broadens it, is the tested point.

Mobile Equipment, Snowplow, and Lessor Endorsements

Several endorsements adjust scope at the margins the exam probes. Mobile equipment (bulldozers, forklifts, cranes) is generally covered by the CGL, not the auto policy, unless it is subject to compulsory auto law or carries equipment that makes it an auto — so an endorsement may move certain self-propelled equipment between the two policies. A lessor/additional insured (CA 20 01) endorsement protects a leasing company as an additional insured and loss payee on autos leased to the named insured. A public-or-livery / for-hire use change requires repricing because the base form contemplates business, not livery, use.

Auto Medical Payments and UM/UIM Choices

Commercial auto can add Auto Medical Payments (first-party medical for occupants regardless of fault) and Uninsured/Underinsured Motorists, with limits and rejection rules driven by the state of garaging. Because limits and mandatory-offer rules vary by state, the covered-auto symbol for compulsory UM (Symbol 6) and the state's financial-responsibility law determine what must be offered. Recognizing that UM/UIM and Med Pay are state-driven add-ons to the business auto program is the scored point.