The Conewago Township-based medical safety device manufacturer formerly was based in Australia and continues to trade its shares on that exchange, as well as on the Nasdaq under the ticker symbol UNIS. CEO Alan Shortall, who is the firm's largest shareholder, made the purchases in the form of CHESS depositary interests, and has expressed interest in purchasing more, according to a news release. CHESS depository interests are a type of security used on the Australian Securities Exchange to allow companies based elsewhere in the world to trade on the market. "I am very pleased with the company's recent progress, and our ability to continue to deliver upon our key business milestones. However, I do not believe that our current strong business position is adequately reflected in the valuation of Unilife's shares," Shortall said in a statement. "Consequently, I have chosen to increase my personal investment in Unilife in an effort to take advantage of this valuation gap."