Activist investor Tanarra Capital is counting on pathology company Healius to deliver more value for shareholders after extracting a desirable price for its imaging business which was sold to private equity for $835 million.

Healius shares rallied 7.5 per cent to $1.73 on Monday after the activist target concluded the auction for Lumus, which was acquired by Affinity Equity Partners. John Wylie’s Tanarra Capital, the second-largest shareholder in the pathology company, conceded Healius got a good enough price to justify letting the asset go.