Shareholders of fallen tech darling Altium have been warned not to bank on a higher bid from Autodesk after the Australian company’s board knocked back a $5.05 billion offer lobbed by the Nasdaq-listed US software giant.

Altium’s board said the $38.50 a share undervalued its business, even though Autodesk’s unsolicited offer included a 41 per cent premium to Friday’s closing price of $27.20 - the last price before Altium entered a trading halt first thing Monday to consider the offer.