Onex Sells Partial Stake in Spirit AeroSystems for 7 Times Cost

All amounts in US dollars unless otherwise stated

Toronto, April 13, 2011 – Onex Corporation (TSX: OCX) and its affiliates (the "Onex Group") announced today that they have sold 10 million shares in Spirit AeroSystems Holdings, Inc. (NYSE: SPR) at a price of $24.49 per share for total proceeds of $245 million. Onex Corporation sold approximately 2.7 million of these shares for net proceeds of approximately $74 million, including carried interest. 

The sale represents approximately 31% of the Onex Group’s remaining equity interest in Spirit AeroSystems. The underwriters have a 30-day option from April 11, 2011 to purchase up to an additional 15% of the shares sold. 

Based on Onex’ cost of $3.33 per share to acquire the business in 2005, this sale resulted in a multiple of over 7 times cost. To date, including the proceeds on this sale and prior realizations, the Onex Group has received $2.5 billion in net proceeds. The Onex Group originally invested $375 million in Spirit AeroSystems and continues to own approximately 16% of the company, which has a current market value of approximately $538 million. 

About Onex 
Onex is one of North America’s oldest and most successful investment firms committed to acquiring and building high-quality businesses in partnership with talented management teams. Onex manages investment platforms focused on private equity, real estate and credit securities. In total, the company manages approximately $14 billion, of which $10 billion is third-party capital. As well, Onex invests its own capital directly and as a substantial limited partner in its Funds. 

Onex’ businesses generate annual revenues of C$36 billion, have assets of C$42 billion and employ more than 238,000 people worldwide. Onex shares trade on the Toronto Stock Exchange under the stock symbol OCX. For more information on Onex, visit its website at www.onex.com. The Company’s security filings can also be accessed atwww.sedar.com.  

Forward-Looking Statements 
This news release may contain forward-looking statements that are based on management’s current expectations and are subject to known and unknown uncertainties and risks, which could cause actual results to differ materially from those contemplated or implied by such forward-looking statements. Onex is under no obligation to update any forward-looking statements contained herein should material facts change due to new information, future events or otherwise.