Stock in the Edinburgh company closed up 87.5p at 512.5p. It plans to cancel its deferred shares, which it says have little economic value, as well as buying back ordinary shares.
Chairman Alastair Ritchie said this should help to narrow the gap between the market price of ordinary shares and the underlying value of the company's assets. Audited net assets of the company in August this year were £6.27m, which John Swan said was equivalent to 1030p per ordinary share.
The board is recommending the share capital proposals to shareholders and hopes to receive backing for them at the company's annual general meeting next month.