Altium's shares have been slapped down after the software company told investors its revenue for the full year would be at the lower end of guidance.
Altium blamed uncertainty surrounding the coronavirus outbreak and subsidiary Octopart's slower first-half start for the slide in forecast, which sent its shares down 14 per cent, or $5.98, to $36.65 by 1235 AEDT.
Revenue will be between $US205 million ($A306 million) to $US215 million ($A321 million), Altium said as it sent its results to the market late on Monday.
"This is due to the emerging uncertainty about the impact of the coronavirus in China and the slower start to Octopart in the first half," Altium said.
Octopart is a search engine for electronic and industrial parts.
It was negatively affected in the first half by the reduced volume in the parts distribution industry, partly due to too much stock.
It was also temporarily hit by changes to the Google search algorithm, which had been rectified, Altium said.
Altium declared an unfranked half year dividend of 20 cents a share, up 25 per cent on the prior half year.