The proposals would mean forcing those member states whose legislation still protects car manufacturers' exclusive right to manufacture and sell visible replacement parts to harmonise their legislation with that of member states including the UK, which allow independent producers to compete in the aftermarket.
The EC estimates visible parts are up to 10% cheaper in countries that have opened up their markets to alternative parts producers, and that independent parts manufacturers account for less than 15% of the EU market.
The draft directive would end design protection in respect of the aftermarket, though car manufacturers would retain all rights regarding parts built into new cars.
Up to 10 European commissioners are thought to be opposed to the plans, including commissioners from Germany, France, Portugal and Slovakia where manufacturers and unions representing their workforces have lobbied against the plans - as well as the commissioner for enterprise. They do not have enough votes to block the proposals, but might succeed in winning at least some protection for carmakers.
ACEA members have argued that the plans would cost them €2.5bn (£1.7bn) a year in revenue, and warned the Commission it could see 50,000 jobs shifted outside Europe, mainly to Taiwan, while making it more difficult to persuade China to crack down on copying of components.
The draft legislation will require the support of the European parliament and a majority of the EU’s 25 member states.