12.5 Commercial Auto Endorsements
Key Takeaways
- Drive Other Car (DOC, CA 99 10) extends liability, med-pay, and UM to named individuals using non-owned autos - essential for corporate-vehicle owners who have no personal auto policy.
- Hired Auto and Non-Owned Auto endorsements fill the rental (Symbol 8) and employee-car (Symbol 9) gaps left by owned-only symbols.
- The Mobile Equipment endorsement and the broadened definition of 'auto' clarify when self-propelled equipment is insured under auto versus general liability.
- Lessor/Additional Insured and Loss Payable endorsements protect leasing companies and lienholders; the lessor is added as an additional insured and given a loss payee interest.
- Rating endorsements such as the experience modification factor (mod) adjust premium up or down from the manual rate based on the insured's own loss history - a mod above 1.00 surcharges, below 1.00 credits.
Why Endorsements Matter
The base Business Auto and Motor Carrier forms leave predictable gaps - rentals, employee cars, executives with no personal auto, leased vehicles, and self-propelled equipment. Endorsements close those gaps and also adjust premium. Each is added by entering the form number on the declarations.
Drive Other Car (DOC) - CA 99 10
The Drive Other Car endorsement extends liability, medical payments, and UM/UIM to named individuals while they use a non-owned auto (one not owned by the named insured). It is designed for the classic gap: an executive who drives only a company-furnished car has no personal auto policy, so when they borrow or rent a car for personal use, nothing responds. DOC supplies that personal-style protection by scheduling the individual.
Hired, Non-Owned, and Lessor Endorsements
| Endorsement | Gap It Closes |
|---|---|
| Hired Auto Physical Damage | Physical damage on rented/borrowed autos (pairs with Symbol 8); may reimburse a rental collision damage waiver (CDW) |
| Non-Owned Auto Liability | Employer's vicarious liability for employee-owned autos (Symbol 9) |
| Lessor - Additional Insured & Loss Payee (CA 20 01) | Adds the leasing company as additional insured and loss payee on leased units |
| Loss Payable Clause | Protects a lienholder's financial interest in a financed auto |
| Mobile Equipment | Clarifies self-propelled equipment insured under auto vs. CGL |
Auto vs. mobile equipment trap: A self-propelled bulldozer used only on a job site is usually mobile equipment (insured under general liability), but once it is licensed for road use or carries permanently attached equipment subject to compulsory auto law, it can be treated as an auto. The definitions decide which policy responds.
The Lessor - Additional Insured & Loss Payee endorsement deserves emphasis: leasing companies require it before delivering a vehicle. It names the lessor as an additional insured for liability arising from the leased auto and as a loss payee for physical-damage proceeds, and it often makes the lessee's coverage primary so the lessor's own policy is not tapped first. Failing to add it is a common errors-and-omissions exposure for producers.
Additional Common Endorsements
| Endorsement | Function |
|---|---|
| Rental Reimbursement (CA 99 23) | Pays a daily/maximum amount for a substitute vehicle after a covered physical-damage loss |
| Pollution Liability - Broadened Coverage for Covered Autos (CA 99 48) | Restores limited coverage for pollutants being transported as cargo |
| Individual Named Insured (CA 99 17) | Extends certain personal-style coverages when an individual owns the policy |
| Audio, Visual & Data Electronic Equipment (CA 99 60) | Schedules and increases the cap on installed electronic equipment |
| Fellow Employee Coverage | Removes the fellow-employee exclusion so co-worker BI is covered |
| Waiver of Transfer of Rights (Subrogation) | Waives the insurer's subrogation against a specified party per contract |
Rating Endorsements and the Experience Modification Factor
Larger commercial-auto risks are experience-rated: the insured's own loss history adjusts the manual premium up or down through an experience modification factor (mod).
- A mod of 1.00 is average - no adjustment.
- A mod above 1.00 is a surcharge (worse-than-average losses).
- A mod below 1.00 is a credit (better-than-average losses).
Worked experience-mod example
A fleet's manual premium is $80,000 and its experience mod is 1.25 (poor loss history).
- Modified premium = $80,000 x 1.25 = $100,000 (a $20,000 surcharge).
If safety improvements drop the mod to 0.85 the next term:
- Modified premium = $80,000 x 0.85 = $68,000 (a $12,000 credit).
A schedule rating plan can then layer additional debits or credits (typically within +/- 25 percent) for risk characteristics like driver training, telematics, and maintenance programs.
Putting Endorsements to Work - Scenario
A contractor owns a fleet (Symbol 1 liability, Symbol 7 physical damage), frequently rents trucks, sends employees on errands in their own cars, leases two trucks from a finance company, and wants its owner protected when borrowing cars personally. The correct stack:
- Symbol 8 + Hired Auto Physical Damage - rental liability and damage.
- Symbol 9 / Non-Owned Auto Liability - employee-car vicarious liability.
- Lessor - Additional Insured & Loss Payee - protects the finance company on the leased trucks.
- Drive Other Car - personal-use protection for the owner who has no personal auto policy.
This is the typical exam framing: a fact pattern hides a gap, and the answer is the endorsement that closes it.
Composite Rating and Premium Audit
Very large fleets are often composite-rated: instead of rating each vehicle, the insurer applies a single rate to an exposure base (such as gross receipts, miles, or payroll) and audits the final premium at expiration. Because vehicles and exposures change mid-term, the inception premium is a deposit premium, adjusted up or down at the premium audit.
Worked audit example: A fleet pays a deposit premium of $120,000 based on estimated 1,000,000 fleet miles at $0.12 per mile. The audit shows actual exposure of 1,150,000 miles.
- Earned premium = 1,150,000 x $0.12 = $138,000
- Additional premium due at audit = $138,000 - $120,000 = $18,000
If actual miles had come in lower, the insured would receive a return premium. Composite rating, experience mods, and schedule credits stack: the manual rate is multiplied by the mod, then adjusted by schedule debits/credits, then trued up at audit.
A corporate executive drives only a company-furnished car and carries NO personal auto policy. When she rents a car on a personal vacation and causes an accident, which endorsement is designed to protect her?
A fleet's manual premium is $80,000 and its experience modification factor is 1.25. What is the modified premium, and what does the mod indicate?