Here's the background: Once a private company has 500 shareholders, SEC rules require the company to register its private stock and disclose financial results.

背景情况：一旦一家私人公司拥有500名股东，那么根据美国证交会的规定，这家公司必须对它的私募股权进行登记，并且披露其财务业绩。

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Private stock offering is a reference to the sale of corporate shares to individual investors without the lengthy registration process required for public offerings.

私人募集是指公司向私人投资者发售公司股份，其注册手续没有公开发行股票所要求的那么冗长。

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Famous people and their private lives are the stock-in-trade of the popular newspapers.

名人和名人的私生活是通俗报纸惯有的内容。

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And it was private. It was not a public company with shares traded on the stock market.

VOA: special.2010.11.28

This can prove difficult, especially when holding shares of an illiquid private stock like Facebook.

FORBES: Facebook's Financials Look Impressive, $50 Billion Valuation Looks High

The Securities and Exchange Commission has allowed these kinds of private stock sales since 1990.

NPR: Turbulent Mortgage Market Ensnares Top Retailers

Robert Beyster, SAIC's founder, has given away nearly his entire company to his employees in the form of private stock.

FORBES: Private matters