UPDATE 1-Activist Elliott ends opposition to CapGemini's Altran bid

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PARIS, March 18 (Reuters) - U.S. activist fund Elliott ended its long resistance to software company CapGemini’s $4.1 billion friendly takeover of smaller rival Altran on Wednesday.

Elliott said in a regulatory filing with France’s AMF regulator that the recent worldwide stock market slump meant it was now prepared to sell its Altran shares to CapGemini.

The activist investor had been holding out for CapGemini to make a higher bid, arguing its offer undervalued Altran.

In January, CapGemini had slightly raised the value of its bid for Altran to 14.5 euros a share from 14 euros, valuing the company at 3.7 billion euros ($4.1 billion). ($1 = 0.9097 euros) (Reporting by Sudip Kar-Gupta and Gwenaelle Barzic; Editing by Alexander Smith)