The Ghost Director of IGS, page-24

MACCA.. the last change in substantial holder notice to IGS was released on 05-Feb-2015
View attachment 111272
Perrier,
“DEFINITION of 'Controlling Interest'When one shareholder or a group acting in kind holds a
high enough percentage of ownership in a company to enact changes at the highest level. By definition, this figure is 50% of the outstanding shares or voting shares, plus one. However, controlling interest can be achieved with less than 50% ownership of the stock if that person/group owns a significant proportion of the voting shares, because in many cases, not every share carries a vote in shareholder meetings.”
Read more: Controlling Interest Definition | Investopedia http://www.investopedia.com/terms/c/controllinginterest.asp#ixzz3qgj34Lhv

Change in substantial holding…..
“Notification Obligations Therefore, under sec. 671B, any shareholder who acquires (alone or with associates) a relevant interest in 5% or more of a company’s shares must disclose that fact by lodging an ASIC Form 603 “Notice of Initial Substantial Shareholder” with the Company and the stock exchange. This lodgement requirement also extends to a shareholder making a takeover bid even if the initial holding is below 5%.
Furthermore, for each 1% (or more) change in holding a Form 604 “Notice of Change of Interests of Substantial Shareholder” must be lodged. And, if the holding falls below 5% a Form 605 “Notice of Ceasing to be a Substantial Shareholder” must be lodged. These Forms must be lodged within 2 business days after they become aware of the transaction or change in % holding and by 9:30am next stock exchange trading day in a takeover situation. If there are a number of Substantial Shareholders with similar or related relevant interests (eg. a corporation and its related corporations, or the manager and trustee of an equity trust), the names can be included in an annexure to the Form. If the relevant interests of a group of persons are essentially similar, they may be referred to throughout the Form as a specifically named group if the membership of each group, with the names and addresses of members is clearly set out in the Form.”

http://www.companysecretary.com.au/board_briefings/SubstantialShareholders.pdf