Marathon on Mobil offer: 'grossly inadequate'

Shades of a Conoco bidding war? Mobil Corporation's bid to buy Marathon Oil Company is prompting speculation of a fight over Marathon similar to last summer's wrangling for Conoco, the world's ninth-largest oil company.

Marathon called Mobil's offer of $3.4 billion ''grossly inadequate.''

Meanwhile, a federal judge in Cleveland has issued a temporary restraining order that prevents Mobil, the second-biggest company in the United States, from buying up to 40 million shares of Marathon stock. The US Justice Department is investigating whether the proposed merger of the two companies would lessen competition.