Rakon has been asked to explain to the Stock Exchange the reason its share price has surged more than 40% this month.
During the period 4 - 27 January, Rakon's share price rose 20 cents from 67 cents, a rise of 42.5%.
The Stock Exchange says Rakon needs to advise whether it continues to comply with the listing rules.
NZX wants an answer by 9.30am on Tuesday.
