Accident at work caused by a third party: what consequences for the employer?

Does the presence of a third party in the occurrence of a work or commuting accident matter? The CPAM recently wanted to take stock of this topic by reminding employers of the importance of bringing such information to its attention.

What is a third party?

Principle: according to article L.454-1 of the Social Security Code, it is a “ person other than the employer or his servants”.

In other words, when it is not an employee of the same company, it is a third party (passerby, delivery person, supplier, customer, subcontractor of the employer, etc.) .

However, this qualification can prove to be complex in certain situations.

What about a temporary worker injured by a permanent employee of the user company to which he is seconded?

As soon as the temporary worker and the permanent employee work under the same management, these two people are considered as colleagues and not as third parties for each other, even if their employer is different (temporary work company for one, user company for the other)

What about the employee injured by the failure of a machine?

If the owner of the machine is not the employer, it is possible to mention a responsible third party, namely the company that owns the machine.

What about an employee injured by an animal?

In this case, same reasoning, the owner of the animal must be identified to be mentioned as third party responsible for the accident.

Exception : in case of willful misconduct or traffic accidentthe notion of third party applies to any person, including an employee of the employer (co-worker).

How to inform the CPAM?

There is an insert specially dedicated to the existence of a third party in the work accident declaration (CERFA n° 14463*03 or directly online via the net-entreprises site). The name, address and insurance company of the third party must be mentioned there.

If the employer is in doubt as to the qualification of the third party, he is advised to complete this insert as a precaution, and it is up to the fund to decide.

What are the consequences for the employer?

The CPAM has a “recourse against third parties” service responsible for recovering the financial consequences from the person responsible for the accident or his insurer.

If the CPAM achieves its goals, the average cost relating to the accident in question will be reduced or completely removed from the base for calculating the employer’s AT contribution rates, depending on the percentage of liability retained.

Note it

For the employee, this does not change anything. He will be compensated by Social Security (which will recover the sums through the employer’s AT contributions and/or through third-party insurance).

Please note that this possibility of obtaining a reduction in AT rates in the presence of a responsible third party is only available to employers in the event of a work accident and not a commuting accident. Indeed, the cost of commuting accidents is pooled at the national level and appears on the AT rates through an incompressible increase set each year by decree, applicable to all companies.

Consequently, the employer has every interest in mentioning a third party in his work accident declaration sent to the CPAM.

In practice, unfortunately, it is not so simple:

  • the employer does not necessarily manage to obtain the name of the responsible third party’s insurance company and even less its contract number at the time of writing the work accident declaration. The CPAM then simply writes to said third party. If he does not answer, the file stops there;
  • some CPAMs require a criminal conviction before initiating recourse against third-party insurance. However, most of these accidents never reach this stage (except extremely serious accident and/or intentional fault);
  • if the request from the CPAM to the third-party insurance remains unanswered, the case ends there.

The employer therefore finds himself completely helpless and suffers from the financial consequences of such accidents solely according to the degree of investment of the CPAMs in the exercise of their recourse against third parties.

To find out more about the declaration and instruction of AT-MPs, Tissot Editions recommends the documentation “Health and safety at work ACTIV”.


Aurore Joly-Aulon

A lawyer specializing in social protection law, Aurore quickly took charge of a legal department within Groupe CRIT. In charge of litigation related to accidents in the…