Activist investor William Ackman, shareholder in Pershing Square Capital Management, announced earlier today that it bought a majority stake in Air Products & Chemicals Inc. for US$2.2 billion. This was the first time the hedge fund manager shared details concerning the deal over the past two months.

The deal gave Pershing Sqaure Capital Management a 9.8% stake in the industrial gas company, making it Air Products' current biggest shareholder. Pershing Square had also planned to buy additional shares if not for the "poison pill" defense adopted by Air Products to prevent takeovers.

Speculation concerning the deal rose around early July when Ackman had begun raising as much as US$1 billion to invest in a project he refused to name. Ackman began purchasing shares early in June and only finished buying until Tuesday this week.

Air Products & Chemicals shared earlier in a statement that it has not communicated with Ackman but looks forward in meeting Pershing Square formally.