The Sarbanes-Oxley Act was passed in 2002 in reaction to accounting scandals by Enron, Tyco, and Worldcom. It radically increased the cost of reporting to public markets. As an unintended consequence, it has delayed IPOs for hundreds of companies, and by the time they IPO, much of the expected increase in value has already been captured by private investors at much lower valuations.
Scott Kupor's guest post in the A16z blog details the implications:
Microsoft went public in 1986 at roughly a $500 million market cap. Today, Microsoft has a market cap of $234 billion. Thus, the public investors in Microsoft have had the opportunity to realize $233.5 billion in market cap appreciation; the private investors had only a $500 million head-start. From IPO, a single share of Microsoft stock has appreciated close to 500x.
Facebook, by contrast, went public in 2012 at roughly a $100 billion market cap. That means that, whatever public stock price appreciation Facebook has over the coming years, private investors have had a $100 billion head-start against the public investors. Even if you were prescient enough to buy Facebook at its public low of approximately a $50 billion market cap, the private investors remain way ahead. If you bought Facebook stock at its IPO, to realize a similar multiple that Microsoft’s public shareholders have earned, Facebook’s market cap would need to reach nearly $50 trillion, roughly the size of the total market capitalization of all publicly-traded companies in the world.
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We are quickly creating a two-tiered investment market—one for wealthy, accredited individuals and financial institutions and a second for the remaining 96% of Americans.
If you are an accredited investor (which the rules define as someone with annual income of at least $200,000 or a net worth of $1,000,000), you can buy or sell privately-held stock of high growth, startup companies via exchanges such as Second Market and SharesPost. If you are an accredited investor, you can become a limited partner in one of over 400 venture capital firms that invest in such companies. If you are an accredited investor, you can buy privately held stock of such companies directly from the issuing companies themselves.
However, If you are among the 96% of Americans that are not accredited investors, you can wait the 9.4 years that it takes for the average startup to go public and miss out on all of the price appreciation in the private markets that inures to the benefit of accredited investors.