NSN said on Monday that some 1,900 people, mostly in Germany, Portugal and China, will be transferred to the new company, which is to be based in Munich.
The sale is part of the Finnish-German joint venture's efforts to focus on its core operations, which revolve around high-speed mobile phone networks.
The deal with the California-based Marlin Equity Partners is to be finalised early next year. The sales price has not been announced.
In 2011, NSN slashed 17,000 jobs, nearly one out of every four employees. Since then it has sold off several product lines.
“During 2012 Nokia Siemens Networks has made tremendous progress in the transformation of our company to being the world’s mobile broadband specialist. Our strategic focus on our core markets has enabled us to concentrate our energy and investment in areas such as LTE where we have strengthened our global leadership position,” said NSN's chief executive Rajeev Suri.
More divestment ahead?
Sami Sarkamies, Senior Technology Analyst at Nordea Markets, predicts that NSN will divest more units.
However he said he was somewhat surprised by the sale as NSN needs some optical technology - where data is transmitted by pulses of light - for its main mobile broadband business. The move may hint the company is preparing itself for further consolidation in the sector by cutting overlaps with other players, Sarkamies suggests.