Beyond its ramifications for Citigroup as a global financial company, the departure of John Reed also raises some questions about e-Citi, the technology development unit of Citigroup that includes its Internet bank, Citi f/i.

The effort was just the latest on the technology front championed by Mr. Reed, who is often described as a visionary in the area. However, e-Citi's development came at a major cost; analysts estimate it has racked up hundreds of millions of dollars in losses over the last two years.

Now that its chief proponent is gone, there are some thoughts inside and outside the company that the business unit, which is headed by Edward Horowitz, may face a tougher sell for some of its projects.

"The real issue is what going is to happen to e-Citi. That was John's baby," said a banking technology source who declined to be identified.

A source at Citigroup said there had been talk in the company that Mr. Reed had wanted to make e-Citi as a separate business, a move that would have given him the kind of cutting-edge opportunity he coveted.

A decision by the Citigroup board against such a spinoff was yet another reason Mr. Reed may have felt he no longer would enjoy his position within the Citigroup management structure, the source said. Citigroup declined to comment.

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