The Competition Commission of India (CCI) levied a penalty of Rs 39.8 crore on Jet Airways, Rs 9.4 crore on InterGlobe and Rs 5.1 crore on SpiceJet, it said in a statement.
The CCI noted in its order that "the airlines acted in a concerted manner" in fixing and revising the fuel surcharge rates, which are a component of freight charges.
The anti-trust watchdog criticised the airlines for using fuel surcharge as a pricing tool which was essentially introduced to mitigate the fuel price volatility.
In 2015, the three airlines were penalised by CCI for the same issue.
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