Dual-class share structures
The cost of control
The trouble with non-voting shares
SHAREHOLDERS in News Corporation have only themselves to blame.
When they entrusted Rupert Murdoch with their money, they knew he would not let them tell him what to do with it.
The Murdoch family owns about 12% of the company but controls almost 40% of the votes, through a special class of shares which have superior voting rights.
Such dual-class share structures are quite common, especially at media firms.
They can shield managers from stockmarket short-termism and hostile takeovers. But they cause problems, too.
Two studies of American firms by Paul Gompers, Joy Ishii and Andrew Metrick, covering the years from 1994 to 2002, found that dual-class firms perform worse than comparable firms where all shares confer equal voting rights.
1994年到2002年，从Paul Gompers，Joy Ishii 和 Andrew Metrick主持的两个关于美国公司的研究发现双重结构的公司比那些实行平等投票的企业，表现要糟糕。
Dual-class firms are fonder of debt than equity, to prevent the dilution of controlling stakes.
Yet surprisingly, their shares do not trade at a big discount on stockmarkets.
A study by Chad Zutter and Scott Smart found that dual-class initial public offerings achieved only slightly lower price-earnings and price-sales ratios than comparable single-class IPOs.
由Chad Zutter和Scott Smart所做的一项调查发现，双阶级公司首次公开发售的股份，比起单阶级公司，本益比和营收比只稍微低了一点点。
Nor does this strange ownership model show any sign of going out of fashion.
There were 12 dual-class IPOs in America last year, not far from the norm for the nine-year period in the 1990s studied by Mr Zutter and Mr Smart.
根据Zutter 先生和 Smart先生的调查，去年在美国首次公开发行股票的公司里有12家是双级公司，与90年代的九年阶段标准差不多。
Dual-class structures are not just a way for press barons to keep their hands on the hatchet with which they threaten governments.
Internet firms love them, too, since they allow founders brimming with self-belief to raise cash without surrendering control.
Google's IPO in 2004 involved two classes of share.
LinkedIn followed suit this year.
The IPO filings of Zynga and Groupon would also grant managers control over voting rights.
Investors who seek long-term gains may be happy to cede control if they think the boss is a genius.
It worked for the holders of B shares in Warren Buffett's Berkshire Hathaway.
手握Berkshire HathawayB型股票的投资者就是，该公司老板是Warren Buffett。
It once worked for investors in Mr Murdoch, too.
But tech punters have not been so lucky.
The number of dual-class firms listed in America fell from 482 in 2000 to 362 in 2002 as the dotcom bubble burst.
If the current internet boom follows a similar path, News Corporation shareholders will not be the only ones feeling second-class.