One of the most prolific activist investors in Japanese companies is targeting Nissan Motor, setting up a corporate standoff that investors hope will translate into a higher stock price.

Nissan Motor shares jumped as much as 6% in early Tokyo trading on Friday after Japan's Diamond Online magazine reported that activist investor Oasis Management had taken a stake in the automaker.

TOKYO (Reuters) - Nissan Motor shares jumped as much as 6% in early Tokyo trading on Friday after Japan's Diamond Online magazine reported that activist investor Oasis Management had taken a stake in the automaker. Nissan shares were last up 4% at 426.7 yen ($2.73), compared with a 0.9% advance on the benchmark Nikkei index.

Nissan Motor shares jumped their most in a decade and a half after an activist investor took a stake in the Japanese carmaker in the midst of turnaround efforts.

Shares in Nissan surged as much as 20 per cent on Tuesday, after a fund managed by activist investor Effissimo Capital Management was revealed to have taken a stake in the struggling Japanese automaker.

By Kantaro Komiya TOKYO (Reuters) -Nissan Motor shares jumped as much as almost 21% on Tuesday after a filing showed activist investor Effissimo Capital Management had taken a stake in the struggling Japanese automaker.