The Tokyo District Court on Thursday sentenced two former members of an investment club at Waseda University to 2½ years in prison, suspended for four years, for manipulating stock prices through Internet trading.

The judges also ordered the two, Masahiro Arie, 36, and Ryuji Nunoura, 33, to return ¥390 million in profit they made over the acts, in addition to a fine of ¥2.5 million each.

Prosecutors had demanded that the two be ordered to return ¥765 million. The defendants' lawyers had argued that the additional imposition should be set at ¥5 million, as that's the actual amount that the two made in profit.

In handing down the sentence, presiding Judge Katsunori Ono said the accused made millions of yen in profit by repeatedly manipulating the prices of stocks mostly listed on the Tokyo Stock Exchange's first section, between February 2013 and August 2013.

The two forced up the prices of four stocks, including that of Kobe Steel Ltd., by making and then canceling large-scale buy orders, he said.

"They abused the financial expertise they had acquired while at the investment club, developing a skillful way (to manipulate stock prices)," Ono said. "Their acts are malicious, as they were repeated."

The judge said the two should pay ¥390 million "so they cannot get away with" the financial gain from their acts, but also said the prosecutors' demand for ¥765 million is "too harsh."