NEW DELHI, Dec 3 (Reuters) - IndiGo, India's biggest

airline, has sued automaker Mahindra and Mahindra for trademark

infringement over its use of "6E" in branding its latest

electric vehicle, legal papers show.

Mahindra in a stock exchange filing, denied

any wrongdoing, saying its recently launched electric vehicles

"BE 6e" and "XEV 9e" had the necessary trade mark registration

and there was no conflict with the "standalone '6E'" branding

used by IndiGo.

IndiGo, which has a 60% share of India's domestic

aviation sector, has used "6E" as its call sign and across all

its branding for years, including its co-branded credit cards,

rewards programme and in-flight magazine.

In its 48-page lawsuit filing, which is not public but

was reviewed by Reuters, IndiGo argues that Mahindra had

"deliberately tried to associate themselves" with the aviation

industry by claiming their car is shaped like a cockpit.

While trademark infringment cases are common in India,

legal disputes between big publicly-traded companies have been

rare.

IndiGo's '6E' trade mark has been exclusively associated

with its services for over 18 years and "is now at risk of

losing its distinctiveness" due to Mahindra's use of 'BE 6e',

the airline said in the court filing.

Mahindra in its stock exchange filing said it is "engaged in

discussions with them (IndiGo) to find an amicable solution." It

has not commented on the contents of the lawsuit.

IndiGo has sought a permanent injunction through its filing

in the Delhi High Court.

With its latest range, Mahindra aims to take on rivals Tata

Motors' Curvv and Hyundai's Creta in India's fast growing

compact SUV range. The segment has grown nearly 20% in the first

six months of the current fiscal year.

India's EV market is small, making up about 2% of total car

sales of 4 million last year, but the government wants to

increase EVs' share to 30% by 2030.