Michelin wary of “complex, potentially misleading” mass-balance claims

Hanover, Germany – Michelin is focused on ensuring the validity of all claims made about the sustainability of its products, particularly with regard to the content of sustainable materials used in its tires.

That was a key message from a Michelin presentation at the recent Tire Technology Expo 2025 conference, which highlighted issues around the use of mass balance to frame claims for product sustainability.

There should be a “direct and relevant” link between the real recycled or renewable content of a product and the claims made for it, Brigitte Chauvin, R&D manager, Michelin set out in Hanover.

While the mass balance approach has benefits, it can allow a “more or less a disconnection with the true composition of the product,” according to Chauvin.

Michelin, therefore, avoids relying on mass balance “due to its complexity and potential for misleading claims”: instead employing a chain-of-custody model that provides clear and simple messaging for end consumers.

Based on 2009 ISO14001, the model categorises chain-of-custody models into a pyramid, with the more stringent models at the top ensure much higher physical connectivity, the R&D leader explained.

The standardised approach “prioritises physical segregation to maintain product integrity,” said Chauvin, and so “purchases only raw materials with a probability of physical connectivity, avoiding those without.”

Factors ranging from batch to site and the use of rolling averages for materials input and carbon credits can impact the interpretation of mass balance, added co-presenter Christophe Durand, VP sustainable material solutions and partnerships.

Sustainability claims can be further compromised where mass balanced assessments are delivered by independent certification companies employing differing methodologies, the presentation also showed.

“We will purchase only raw materials with a probability of connectivity, meaning that with some types of mass balance [materials], we will not buy them, nor report them,” said Durand.

“This is key to our strategy, he continued. “This is how we select what we believe will be technologies that are going in the direction to change the industry toward the greener solutions.

“We wanted to select physical connection, because in the end, we want to make sure the [sustainable material] is actually in our tires. Buying [carbon] credits is not bad at all: the point is, it's totally different claim.”

“When it gets to the consumer, the message has to be simple and crystal clear,” concluded Durand, stressing that any misleading claim is “such a high risk to the brand” and something society will not accept.

We will report further on this presentation and topic in the May/June issue of European Rubber Journal magazine.