Shai Agassi, who was scheduled to become co-chief executive of SAP, is leaving the company on 1 April.

The loss of the president of the product and technology group will surprise many IT professionals who have bought into the technology roadmap spearheaded by Agassi, including NetWeaver and SAP’s on-demand initiatives.

The move is not related to the legal action being brought by enterprise software rival Oracle against SAP, the German comany insisted.

"It looks like the new guard is being pushed out by the old guard," said Denis Pombriant, managing principal at Beagle Research.

Agassi was set to become co-chief executive of SAP when Henning Kagermann leaves the top post. However, SAP chairman Hasso Plattner asked Kagermann to retain his position until 2009 instead of leaving the job this year, so he could continue to lead the company through planned new product launches.

"Most likely, [Agassi] wasn't happy when I asked [Kagermann] to stay until 2009," Plattner said, in a briefing on the changes. "He has told me this is not the last thing he wants to do in his life."

Rather than wait additional years to take on the leadership position at SAP, Agassi had decided to leave the company now to commit his time to other interests. He would pursue new business opportunities in alternative energy sources and environmental policy, SAP said.

Leo Apotheker, currently president of customer solutions and operations, will immediately take on the new role of deputy chief executive. Apotheker was previously lined up to be co-chief executive with Agassi.

"I really want to reiterate again that Shai leaves on good terms," Plattner said. Agassi will continue to serve as a special consultant with Plattner on technology innovations and competitive trends, maintaining his office at SAP's California campus, Plattner said.

The NetWeaver and on-demand initiatives Agassi developed will result in a change in the financial model at SAP from a licensing model to an on-demand model, he said. "The revenue streams are going to look very different and that can be very challenging and upsetting to major investors," Pombriant noted. SAP may struggle in the face of that transition without Agassi's leadership, he said.

The executive changes are not at all related to the most recent lawsuit that Oracle filed against SAP, charging SAP with stealing corporate information, Plattner said.

David Bradshaw, principal analyst at Ovum, said the most damaging possibility for SAP would be that Agassi could be recruited by a competitor. But he said: “Even without Agassi going to a competitor, this is still a big loss for SAP. He was a highly charismatic and highly visible driving force for change within the company. He championed the development and adoption of its NetWeaver architecture, turning it into a key part of the company’s path and a vital part of its product, marketing and competitive strategy going forward."

Bradshaw said: "There’s no lack of talent in SAP without him – indeed there are plenty of capable hands to grasp the career opportunities such a senior departure throws up - but some of the excitement will be gone. Kagermann’s oft repeated mantra that SAP is about the boring stuff could come to apply to the company itself.”

He added: “From the customers' viewpoint, the only change is that SAP’s user conferences will get duller. Agassi is a great speaker who could make the most turgid and boring material into a riveting presentation.”