All Nippon Airways Co. says it was "unnatural" to see trading of its stock climb to a three-month high a day before the company announced a public offering last week.
"We recognized that it's unnatural," ANA spokesman Ryosei Nomura said, adding ANA has no plan to take action after underwriters assured that they didn't leak information.
ANA announced a ¥211 billion share sale at 4 p.m. July 3. Investors traded 24 million ANA shares on July 2, the most since March 27, according to data compiled by Bloomberg. The stock declined as much as 2.7 percent on July 2 before closing 0.9 percent lower, while the benchmark Topix dropped 0.1 percent.
Regulators going after insider trading learned that investors short-sold stocks using tips from underwriters before four public offerings in 2010. Democratic Party of Japan lawmakers last week urged a wider probe after finding spikes in transaction volumes before 25 issuances were announced, including a 2009 sale by ANA.