According to department sources, the companies have not declared the correct assessable value of final products cleared by them. The excise department's initial estimates have put duty evaded at about Rs 11.50 crore.

The companies have not included the landed cost of free of cost (FoC) items in the assessable cost of their final products, which has resulted in under-valuation of the products, sources added.

Sources alleged that Maruti has been in the know of the fact that full value of the free components have not been included in the final value of the products.

Others who have been issued the show cause include Bharat Seats Ltd, Jai Bharat Maruti Ltd, Caparo Maruti Ltd, Mark AutoIndustries Ltd, Krishna Maruti Ltd, Bajaj Motors (P) Ltd, Mark Exhaust Systems Ltd, Jay Yushin Ltd, Dynamic Industries, Sun Vaccum Formers Ltd and Engineers Combine.

Maruti provides certain components and inputs free of cost to some of the companies on payment of duty for the manufacture of their final products which are supplied back to Maruti. The companies avail of Modvat credit on these final products.

The final products manufactured by these companies are used by Maruti either as parts of original equipment (OE) for further manufacture of vehicles or cleared as spares. In the former situation, Maruti is eligible to avail Modvat credit of duty paid by the companies.