The combination of decreasing interest rates, loosening lending standards and regulatory changes for publicly traded companies (specifically the Sarbanes-Oxley Act) would set the stage for the largest boom private equity had seen. Marked by the buyout of Dex Media in 2002, large multi-billion dollar U.S. buyouts could once again obtain significant high yield debt financing and larger transactions could be completed. By 2004 and 2005, major buyouts were once again becoming common, including the acquisitions of Toys "R" Us, The Hertz Corporation, Metro-Goldwyn-Mayer and SunGard in 2005.
As 2005 ended and 2006 began, new "largest buyout" records were set and surpassed several times with nine of the top ten buyouts at the end of 2007 having been announced in an 18-month window from the beginning of 2006 through the middle of 2007. In 2006, private equity firms bought 654 U.S. companies for $375 billion, representing 18 times the level of transactions closed in 2003. Additionally, U.S. based private equity firms raised $215.4 billion in investor commitments to 322 funds, surpassing the previous record set in 2000 by 22% and 33% higher than the 2005 fundraising total The following year, despite the onset of turmoil in the credit markets in the summer, saw yet another record year of fundraising with $302 billion of investor commitments to 415 funds Among the mega-buyouts completed during the 2006 to 2007 boom were: Equity Office Properties, HCA, Alliance Boots and TXU.
In July 2007, turmoil that had been affecting the mortgage markets, spilled over into the leveraged finance and high-yield debt markets. The markets had been highly robust during the first six months of 2007, with highly issuer friendly developments including PIK and PIK Toggle (interest is "Payable In Kind") and covenant light debt widely available to finance large leveraged buyouts. July and August saw a notable slowdown in issuance levels in the high yield and leveraged loan markets with few issuers accessing the market. Uncertain market conditions led to a significant widening of yield spreads, which coupled with the typical summer slowdown led many companies and investment banks to put their plans to issue debt on hold until the autumn. However, the expected rebound in the market after 1 May 2007 did not materialize, and the lack of market confidence prevented deals from pricing. By the end of September, the full extent of the credit situation became obvious as major lenders including Citigroup and UBS AG announced major writedowns due to credit losses. The leveraged finance markets came to a near standstill during a week in 2007. As 2007 ended and 2008 began, it was clear[by whom?] that lending standards had tightened and the era of "mega-buyouts" had come to an end. Nevertheless, private equity continues to be a large and active asset class and the private equity firms, with hundreds of billions of dollars of committed capital from investors are looking to deploy capital in new and different transactions.
Although the capital for private equity originally came from individual investors or corporations, in the 1970s, private equity became an asset class in which various institutional investors allocated capital in the hopes of achieving risk adjusted returns that exceed those possible in the public equity markets. In the 1980s, insurers were major private equity investors. Later, public pension funds and university and other endowments became more significant sources of capital. For most institutional investors, private equity investments are made as part of a broad asset allocation that includes traditional assets (e.g., public equity and bonds) and other alternative assets (e.g., hedge funds, real estate, commodities).
Most institutional investors do not invest directly in privately held companies, lacking the expertise and resources necessary to structure and monitor the investment. Instead, institutional investors will invest indirectly through a private equity fund. Certain institutional investors have the scale necessary to develop a diversified portfolio of private equity funds themselves, while others will invest through a fund of funds to allow a portfolio more diversified than one a single investor could construct.