Three of JPMorgan's top investors undecided on Dimon's roleL: WSJ

JPMorgan Chase & Co has yet to convince three of its largest shareholders to support the company in an upcoming vote on whether Jamie Dimon should retain both his CEO and Chairman titles, the Wall Street Journal said.

Some investors are pushing for a separation in Dimon's roles and seeking more oversight due to the "London Whale" trading losses. Votes on the non-binding recommendation will be tallied on May 21.

The investors, BlackRock Inc , Vanguard Group Inc and Fidelity Investments - which together control 12 percent of the shares - are still on the fence, the Journal said quoting people close to the firms. (http://r.reuters.com/kek87t)

Two of the bank's top 10 shareholders have told Reuters that they will consider voting in favor of the proposal.

JPMorgan's $6.2 billion loss stemmed from bets by London-based Chief Investment Office trader Bruno Iksil on an index for credit default swaps. His outsized positions earned him the nickname "London Whale" from hedge fund traders taking the other sides of his positions.

The three investors and JPMorgan were not immediately for comment outside U.S. business hours. The bank's board has said it opposes the shareholder proposal and that the company's handling of the trading loss shows its current governance works.

(Reporting by Pallavi Ail in Bangalore; Editing by Edwina Gibbs)