In the filing, Blackstone outlines several reasons for its move to the public market. "We have decided to become a public company: to access new sources of permanent capital that we can use to invest in our existing businesses, to expand into complementary new businesses and to further strengthen our development as an enduring institution; to enhance our firms valuable brand; to provide us with a publicly traded equity currency and to enhance our flexibility in pursuing future strategic acquisitions… ."

Current management will have the first option to buy, trade Blackstone shares for the publicly traded ones, before the remaining shares are opened to the public market. "Prior to this offering we will enter into an exchange agreement with the holders of partnership units in Blackstone Holdings (other than the Blackstone Group LP's wholly owned subsidiaries) so that these holders may exchange their Blackstone Holdings partnership units for the Blackstone Group LP common units on a one-for-one basis."

The filing states, "Unlike the holders of common stock in a corporation, our common unitholders will have only limited voting rights and will have no right to elect our general partner or its directors. Moreover, immediately following this offering our senior managing directors will generally have sufficient voting power to determine the outcome of those few matters that may be submitted for a vote of our limited partners, including any attempt to remove our general partner."

As of the beginning of March, Blackstone had $78.7 billion of assets under management, a total that has increased significantly since 2004 when the firm had $31.7 billion of assets. While some of the increase is due to individual property purchases, Blackstone of late has been involved in a number of mergers and acquisitions, including most recently the $39-billion purchase of Equity Office Properties Trust. Based on the SEC filing, Blackstone does not appear to be done with large M&A transactions. Among its listed risks of going public, Blackstone mentions its recent propensity for large-sized investments and the complexities that accompany them and later outlines how large-capitalization buyouts are "compelling opportunities" for the firm. "Given our global reach, our network of skilled former senior corporate executives, the size of our capital pool and the depth of our transaction and financing expertise, we believe that we are one of a limited number of firms favorably positioned to participate in this large-capitalization market, which has been the fastest growing segment of the buyout industry."

Beyond the purchase of EOP, Blackstone has recently purchased Trizec Properties Inc. and Trizec Canada Inc. for a $9-billion deal; Cendant Corp.'s Travelport for $4.3 billion; CarrAmerica Realty Corp. for $5.6 billion; and MeriStar Hospitality Corp. for $2.6 billion.