The move is part of JPMorgan's efforts to close the all-share deal by the middle of next month and stave off any attempts to delay it. Market pressure has already forced JPMorgan to raise its original offer of $2 per Bear share to $10.
The reorganisation of the investment banking business comes as JPMorgan -suffered the defection of John Coyle, the head of its private equity banking unit, to Permira, the UK buy-out group.
Under the new structure, investment banking, mergers and acquisitions, and capital markets will be run jointly by Steve Black and Bill Winters, the current co-heads of JPMorgan's investment bank.
Former Bear bankers will hold just five of the 26 top positions underneath Mr Black and Mr Winters, leaving JPMorgan's executives in the driving seat of the investment bank.
The blueprint - which was revealed to employees yesterday - does not mention the future of Alan Schwartz, Bear's chief executive, and Sam Molinaro, chief financial officer.
"There are still ongoing discussions with other key leaders on their roles," JPMorgan said yesterday in a memo to employees.
Among the top Bear bankers to stay with the combined firm are Jeff Mayer, who becomes vice-chairman of the investment bank, and Jeff Urwin, head of investment banking in the Americas.
People close to the situation said JPMorgan's senior executives, led by the chairman and chief executive Jamie Dimon, were turning their attention to the number of job cuts needed among Bear's 14,000 employees.
They added that no decision was imminent but the new business heads were expected to come up with staffing estimates over the next few weeks.
Separately, Permira said Mr Coyle would be the joint head of its US operations with Tom Lister, who was last year named as co-managing partner, replacing Damon Buffini at the helm of the buy-out firm's day-to-day operations.
Mr Coyle joined JPMorgan in 1988 after an MBA at Columbia University and a decade later moved to London to found the bank's buy-out financing business in Europe, where it established a dominant position.
Permira said his appointment would allow Mr Lister, a former partner at Forstmann Little, the now-defunct US buy-out house, to spend more time on running the firm.
Permira has sold much of its US portfolio, such as its stake in satellite operator Intelsat.
However, it still owns Freescale, the semiconductor company bought for $17.6bn in 2006 by a consortium including Blackstone, TPG Capital, and the Carlyle Group.
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