The Swede had a 14.7% stake in the Stirling firm but sold 2.6 million shares to reduce that to 9.4% earlier this week.
Yesterday he offloaded a further 850,000 shares, leaving him with a 7.7% stake in the business.
After starting the year at 4.75p Superglass shares have climbed in recent days to close the week at 6.12p.
The business reported flat revenue in the 12 months to August 31, and narrowed operating losses from £4.3 million to £2.5m.
It is implementing a major turnaround plan to shave around £1.4m from its annual costs.