Michelin held to have dominant position in market of replacement tires of heavy vehicles. Michelin argued that relevant market was broader, and was market for replacement tire in general. First, looked at Interchangeability and said that clearly there is no interchangeability, but then went on to see if there could be Interchangeability from point of view from supplier! I.e if you are producer of light vehicles tiers, can switch to heavy vehicles tiers. HELD: considerable investment would be needed to modify a production plant that manufactures light tiers to produce instead to produce heavy tires. Comment: slightly confusing, why did they have to go to look at supply, they don't do this consistently anyways
