LONDON (AFX) - Shares in the mid-cap technology group Psion PLC were down nearly 30 pct, wiping almost 120 mln stg from its market value, as the group realised significantly less than expected from the sale of its stake in Symbian to mobile phones giant Nokia.

Psion revealed it is selling its 31.1 pct share in the software group for 135.7 mln stg. Research issued in December by Merrill Lynch valued Symbian at 780 mln in total and the UK group's holding at over 240 mln.

Even taking the conservative calculation of ABN Amro, published in research issued last November, Symbian's price tag comes out at 592 mln stg, making the Psion stake worth 184 mln.

Additionally, there have been reports in the last several months suggesting Nokia might launch a 400 mln stg bid for Psion as a whole in order to take control of Symbian.

"By the share price reaction, you could say today's news is disappointing," said one equity analysts who asked not to be named.

At 8.50 am, the stock was down 27-3/4 pence, or 29 pct, at 68.

Privately owned Symbian was formed in June 1998 to develop an industry standard operating system for mobile phones.

ijl/rn