Genedrive PLC (LON:GDR) chairman Ian Gilham has invested £10,000 of his own money into the diagnostic devices maker.
The company confirmed on Thursday morning that Gilham, who has been chairman for five years, bought 51,250 shares at an average price of 19p per share.
The purchase takes his total stake up to 0.93%.
Investors tend to like it when directors back their own companies, taking it as a show of faith in the business' future.
Shares jumped 7.7% to 18.9p on Thursday morning, valuing the company at £6.4mln.
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