12.5 Commercial Auto Endorsements

Key Takeaways

  • Drive Other Car (DOC) extends liability and medical payments to named individuals driving non-owned autos - vital for executives with no personal auto.
  • Hired Auto and Non-Owned Auto coverages (symbols 8 and 9) close the gaps left by owned-only symbols.
  • The Mobile Equipment endorsement and rental reimbursement, towing, and lease-gap endorsements tailor the policy to the risk.
  • Additional insured and waiver-of-subrogation endorsements satisfy contractual requirements with clients and lessors.
  • An experience modification factor adjusts premium up or down based on the insured's loss history versus expected losses.
Last updated: June 2026

Why Endorsements Matter

The Business Auto Coverage Form is deliberately modular, so endorsements are how a producer closes gaps and meets a client's contracts. The exam tests both what each endorsement does and which gap it fills.

Drive Other Car (DOC)

The Drive Other Car (DOC) endorsement extends liability and medical payments (and optionally UM/UIM and physical damage) to named individuals while they drive a non-owned auto.

It solves a classic problem: a company executive drives only company cars and carries no personal auto policy. Without DOC, that individual has no coverage when borrowing or renting a car for personal use, because the company policy covers the entity, not the person's personal driving. DOC effectively gives the named person personal-auto-like protection.

Hired, Non-Owned, and Physical-Damage Endorsements

Endorsement / CoverageWhat It Adds
Hired Auto (Symbol 8)Liability/physical damage for rented, leased, or borrowed autos
Non-Owned Auto (Symbol 9)Employer's vicarious liability when employees use their own cars for business
Hired Auto Physical DamageComprehensive/collision on rented vehicles (often by audit)
Rental ReimbursementDaily rental cost while a covered auto is repaired after a covered loss
Towing and LaborRoadside towing/labor at the disablement site
Auto Loan/Lease GapThe 'gap' between ACV and the remaining loan/lease balance after a total loss
Mobile EquipmentTreats certain equipment as autos when it must be

Exam trap: Symbol 9 protects the employer, not the employee; the employee's own policy is primary for their own car.

Contractual Endorsements

Clients and lessors frequently require coverage modifications by contract:

  • Additional Insured - extends the named insured's liability coverage to another party (a lessor of a leased auto, or a client) for liability arising from the named insured's autos.
  • Waiver of Transfer of Rights of Recovery (Waiver of Subrogation) - the insurer agrees not to subrogate against a specified party, honoring a contract the insured signed.
  • Loss Payee - names the lender or lessor to receive physical-damage loss payments.
  • Primary and Non-Contributory wording - makes the named insured's policy pay first and not seek contribution from the additional insured's own insurance.

These rarely change the named insured's own protection; they redirect rights and add parties to satisfy a written agreement.

Commercial Auto Endorsements and Worked Traps

The Business Auto Coverage Form is tailored with endorsements that expand insureds, autos, and coverages. Frequently tested ones include Hired Auto and Non-Owned Auto liability (covering autos the business rents or employees' personal cars used for business), Drive Other Car (DOC) for executives without a personal auto, Mobile Equipment, and Pollution Liability – Broadened Coverage for Covered Autos (CA 99 48) for cargo-related pollution.

EndorsementWhat it adds
Hired & Non-Owned AutoLiability for rented/borrowed and employees' autos
Drive Other Car (DOC)Personal-auto-style coverage for an exec with no owned car
CA 99 48 (Pollution)Broadens pollution for covered-auto cargo spills
Individual Named InsuredAdds personal-auto-style coverages for an individual owner
Lessor – Additional InsuredProtects a vehicle lessor as additional insured/loss payee

The covered-auto symbols (1-9) on the declarations interact with these endorsements: symbol 8 designates hired autos and symbol 9 designates non-owned autos, so a business that does not own vehicles can still buy liability using symbols 8 and 9 plus the hired/non-owned endorsement.

Worked scenario: A consulting firm owns no vehicles, but employees drive their own cars on client visits and the firm occasionally rents vans. Using symbol 8 (hired) and symbol 9 (non-owned) liability, the firm protects itself against suits arising from those uses — but the endorsement does not provide physical damage on the employees' personal cars; that remains each employee's own PAP. This division of physical-damage responsibility is a common exam trap.

Test Your Knowledge

A corporate vice president drives only company-owned vehicles and carries no personal auto policy. While on vacation she rents a car and causes an accident. Which endorsement is designed to provide her with liability and medical payments coverage?

A
B
C
D

Experience Modification

Larger commercial-auto accounts are priced using an experience modification factor (mod), which compares the insured's actual losses to the expected losses for a business of its type and size.

  • A mod of 1.00 is average.
  • A mod below 1.00 (a credit) means better-than-expected experience and lowers premium.
  • A mod above 1.00 (a debit) means worse-than-expected experience and raises premium.

Worked example

The manual (base) premium is $40,000 and the insured's experience mod is 0.85.

Modified premium = $40,000 x 0.85 = $34,000 - a $6,000 credit for good loss history.

If instead the mod were 1.20, the premium would be $40,000 x 1.20 = $48,000, an $8,000 debit. The mod rewards safe fleets and penalizes loss-prone ones, giving the insured a direct financial incentive to control claims.

Endorsement Selection by Scenario

The exam often asks which endorsement solves a stated problem. Drill the pattern:

ScenarioRight Endorsement
Executive drives only company cars, no personal autoDrive Other Car (DOC)
Employees run errands in their own carsNon-Owned Auto (Symbol 9)
Company rents trucks at peak seasonHired Auto liability + Hired Auto Physical Damage
Leased vehicle totaled with loan balance above ACVAuto Loan/Lease Gap
Client contract requires being named on the policyAdditional Insured
Contract bars the insurer from recovering against the clientWaiver of Subrogation
Vehicle disabled on the highwayTowing and Labor

Trap: Symbol 9 protects the employer's vicarious liability, not the employee's own car - the employee's personal policy remains primary for damage to that vehicle.

Audit, Deposit Premium, and Reporting

Many commercial-auto endorsements interact with how the policy is rated and audited. Hired-auto coverage is frequently rated on a cost-of-hire basis (the dollars spent renting vehicles), so the final premium is set at audit rather than at inception.

TermMeaning
Deposit premiumEstimated premium paid at the start of the term
AuditEnd-of-term review of actual exposure (units, cost of hire)
Earned premiumThe portion the insurer has earned as time elapses

A fleet that adds five trucks mid-term will owe additional premium at audit; a fleet that sheds vehicles may receive a return premium. Understanding that the deposit premium is an estimate - reconciled later to actual exposure - explains why commercial-auto accounts can generate large audit bills and is a reliable test concept.