What is a homologated tyre ?

Homologated Tyres 

It is a tyre that has been developed in conjunction with a car manufacturer  to meet the requirements and standards of the car manufacturer. The tyre meets minimum efficiency requirements in various characteristics such as braking, noise and grip under various conditions. The entyre process, from the beginning to the manufacturing of the tyre, can take about 3 to 4 years. It should be noted that original equipment tyres are not necessarily approved and vice versa.

Example: 

AU: AUDI  

AZ : FIAT, SUBARU, ALFA ROMEO and TOYOTA  

Homologation list HERE 

What is the advantages of a homologated tyre for my vehicle?

By purchasing a tyre homologated for our brand of vehicle, it is ensured that we get the most out of the characteristics desired by the manufacturer. For example, for a Tesla, it is ensured that the noise level of the tyre will not be higher than what was originally intended and for a Porsche, we will have at least equal performance to what was originally intended.

What is the difference between the homologated version and the "standard" version?

There could be major construction differences between 2 versions of the same product homologated for 2 different vehicles. The size (e.g. 225/45R18 98 W) could be the same but there can be many differences such as: 

- Compound (softer, harder etc) 

- Internal construction (stiffness of the carcass, footprint) 

- Weight 

- Tread depth 

Here is an example of the exact same tyre model from Pirelli in the exact same size and specs: P-ZERO size 305/30ZR20, one is homologated for an Audi, the other one for a jaguar 

Is it mandatory to have the homologated tyres for my vehicle?

No, although it is ideal, there are no regulations that require you to use them. It is also permitted to use a tyre approved for another brand if it is of the same size and exceeds the load and speed ratings of your vehicle.