JPMorgan Asset Management (Japan) will request that Japanese companies raise the share of women on their boards to at least 30%, President Shoichi Okoshi has said.

The Japanese affiliate of U.S. financial giant JPMorgan Chase plans to adopt the threshold within several years, as a criterion for deciding whether to vote for companies' proposals for board member appointments at shareholders meetings, Okoshi said in a recent interview.

"Diversity is indispensable for boards to have effectiveness" in corporate governance, Okoshi said.