Oasis Management Co. said CVC Capital Partners’ buyout proposal for Toshiba Corp. is too cheap, sending shares of the Japanese conglomerate higher. The Hong Kong-based hedge fund said the price of 5,000 yen per share mentioned in media reports is below fair value, which should be more than 6,200 yen a share. It urged Toshiba’s board to conduct a fair and open process for all parties interested in buying the company.