Ulster Bank has sold its stockbroking subsidiary, NCB, to a group of its senior management and the corporate finance specialist Key Capital, in a deal believed to be worth up to €20 million.

NCB's founder Mr Dermot Desmond's investment vehicle, IIU, has stepped in to underwrite the institutional portion of the deal and will exit when an estimated 20 per cent of the brokerage is ultimately sold to an investment institution.

Several potential investors have already expressed an interest in taking up that stake and the new owners will pursue those discussions.

The UK venture capital group, Alchemy, has been mentioned as one interested party.

The management buyout in association with Key Capital ends more than a year of speculation about the ownership of the stockbroker after Ulster Bank's parent, Royal Bank of Scotland, signalled its intention to sell non-core businesses.

Announcing the sale yesterday, Ulster Bank chief executive, Mr Martin Wilson, said he believed it was in the best long-term interest of NCB's customers and staff.

NCB chief executive, Mr Conor O'Kelly, said the new owners were determined to build on what was a very successful and resilient brand.

"We are glad that, subject to regulatory approval from the Irish Financial Services Regulatory Authority, the ownership uncertainty that has overhung the business for the past number of months has now been brought to an end and we look forward with confidence to the future."

Key Capital's partners, Mr Conor Killeen, Mr Liam Booth, Mr Kyran McStay and Mr Ken Mintern, will now join NCB's management team, and Mr Killeen will assume the position of NCB chairman. Key Capital will now effectively cease trading and will be subsumed into NCB.

Talks between the two groups were initiated about a month ago after the failure of an earlier management buyout attempt.

Mr Killeen said the group was attracted by NCB's domestic and international platform which would offer significant opportunities for its clients.

"We were particularly impressed with the culture of the organisation. Any other firm in its position over the past 12 months would have folded but they really traded through it. They are really committed to each other," Mr Killeen said.

Mr Desmond said he was happy to assist the new NCB team to conclude a deal as soon as possible. "The deal is good for the firm and the market as it will ensure that NCB remains a strong and independent firm," he said.

One of NCB's key executives, Mr John Butler, the managing director of the firm's corporate finance unit, will leave the business at the end of this financial year to pursue other interests, according to the statement.

NCB employs 150 staff and has a substantial institutional stockbroking, wealth management, corporate finance, bonds, moneybroking and funds listings business.

Key Capital was established in 2001 as a specialist corporate and capital markets advisory group and employs nine people.

Its managing director, Mr Killeen, was formerly global head of equities at Dresdner Kleinwort Wasserstein and before that was global head of equity capital markets at UBS.

The company recently advised Benchmark Capital and the management of Alphyra, the e-payments company, on the €89 million buyout of Alphyra.

Mr O'Kelly said the deal brought independence to NCB, a quality that was more valued by investors in the current environment.

Its two biggest rivals, Davy and Goodbody, are owned by Bank of Ireland and AIB respectively.