It's something of an axiom in the markets that investors don't like to see directors selling off large bundles of shares. It sends the wrong signals about the directors' confidence and belief in the company and generates doubts over the long-term direction of the share price. The president of Parthus, Kevin Fielding, hasn't taken long to jump on the share sale bandwagon when he pocketed £624,000 sterling after selling 600,000 shares on the London market. Selling such a large number - one-third of his stake - at such a low price certainly sends the wrong signals.

Remember, this is the same man who only joined the Parthus board late last year, is paid $180,000 a year, has options on 2.7 million Parthus shares - which can be exercised at $1.08, and also gets undisclosed dividend payments from patent companies associated with Parthus. Did he really need to sell off 600,000 shares at not much above Parthus's flotation price? That sale triggered a 4 per cent fall in share price and left it 14 per cent off its current year high of 108p sterling.

Add in the £40 million plus that Brian Long, Peter McManamon and Michael Peirce got from last October's secondary share offering at 210p a share - more than twice the current level - and it's pretty obvious why there is a degree of dissatisfaction with the selling of shares by Parthus directors.