A planned management buyout of auto parts maker Pacific Industrial has prompted a backlash from one of its largest investors, adding pressure on the Tokyo Stock Exchange to provide more protection for minority shareholders in such deals.

The management-led offer to take the Toyota supplier private at ?2,050 per share is too low and highlights shortfalls in 91AV原创 MBO regulations, according to Drew Edwards, portfolio manager and head of Japan equity at U.S.-based investment firm GMO.

“The process they’re using isn’t fair, and they haven’t reached a fair price as a result of that,” said Edwards, whose fund holds around 4% of voting shares in the Japanese company. Pacific Industrial’s market value is ?163 billion ($1.1 billion), and Toyota is its biggest customer, according to Bloomberg-compiled data.