With all the hubbub surrounding the IPO of professional social networking site LinkedIn, along with rumored deals involving Facebook and Twitter, it’s worth remembering that there are some companies that will probably never go public and probably are unlikely to sell themselves.

Some, such as media company Bloomberg L.P.,  are in businesses controlled by their founders or their heirs and do not see the need to be answerable to public shareholders.  Others, Including fast food chicken chain Chick-Fil-A, may be worried about comparisons to large public competitors such as McDonald’s Corp. (NYSE:MCD).   Some including Perdue Farms probably wouldn’t go public now because investors remain concerned about rising commodities prices.  Cargill, the agribusiness giant, may not see the point in going public since it already reports its earnings since its bonds are publicly traded. Cargill is the largest private firm in the US.  Update: A company spokeswoman says that the firm has voluntarily reported its earnings for years and that it has nothing to do with its bonds being traded on the open market.

Then there are the expenses of being public.  When Sarbanes-Oxley was enacted after a wave of corporate scandals in the late 1990s including Enron and WorldCom,  many business leaders argued that the law’s costs –– which averaged about $3 million, far exceeding the SEC’s estimates of $91,000 excluding audit fees — were not worth its benefits.  Some make that same argument today even though the public largely favored the law when it was enacted.

“Paradoxically, the companies that were most aggressive in manipulating earnings were the companies that benefited the most from SOX,” writes Cheryl L. Wade, Dean Harold F. McNiece Professor of Law at St. John’s University School of Law, in a 2008 article in the Loyola University Chicago Law Journal. “Because of SOX, investors believed the information they received was more reliable.”

Despite all the hoopla surrounding the big tech IPOs and the growth of the private stock market,  the IPO market needs to be kept in perspective.  As Renaissance Capital noted in January,  China surpassed the US in 2010 in the IPO market and China-based companies accounted for one-third of US IPOs.   Those figures were helped by the mammoth $16 billion General Motors IPO.   It was the only U.S.-based company to rank among the world’s biggest IPOs.

“Despite GM’s blockbuster offering, average deal size fell 28% from 2009 to $251 million as several high-profile buyout firms pushed out their IPO plans, most notably Nielsen, HCA and Toys “R” Us. Of note, only five US companies raised more than $500 million in their IPOs, well below the trailing five-year average of 13 companies,” Renaissance Capital says.

Indeed, US IPOs showed a total return of 25% in 2010, which though better than 2008’s -33% and 2009’s 16% still lagged behind 2006’s 26% gain.  Renaissance expects the 2011 IPO to increase this year.  Venture capitalist William Quigly recently opined that the next 10 years will be “great” for tech company founders and the venture capitalists who back them.

Maybe Quigly has a point that addresses the high-fliers such as Facebook (more than $200 billion) valuation, Groupon’s estimated value of as much as $20 billion and Twitter’s $7.7 billion, that’s not the case for all companies.  Some prefer to stay private because they don’t need the money or the aggravation.  Here is our picks for firms that have never gone public and may stay private forever.   It is in no particular order.

1. Bloomberg L.P., the media company controlled by New York Mayor Mike Bloomberg, has been the subject of buyout rumors for years.   I heard plenty of them myself when I worked there for seven years.  None of them, including one involving Microsoft Corp. (NASDAQ:MSFT), proved to be true.   Bloomberg, who owns a 68% stake in the company, has received buyout offers for years and turned them down.   Fortune reported in 2007 that the mayor held discussions with private equity players that went nowhere.

In any case, there is a pointed question to be asked of Mike about his sale explorations, and Fortune asked it in a phone conversation with him in January: “Considering how proud you are of this company, could you really sell it to a private-equity firm?” And he answered, “No, I couldn’t.”

Besides, what would be the point?   Bloomberg already is quite successful and has been one of the few media companies that have continued to expand during the economic slowdown.   It even bought BusinessWeek in 2009 and has turned around the moribund publication.   In 2008, it acquired Merrill Lynch’s 20% stake for $4.5 billion, which valued the entire firm at $25 billion.  The value has probably increased  more since then.   Bloomberg the business person decided years ago not to discount his product even though that’s what his rivals did such as Dow Jones and Reuters did.    Customers thought the service was worth the money.  Revenue at the New York-based company reportedly rose from $4.6 billion in 2006 to $6.25 billion in 2010, according to Fortune and Forbes. Integrating Bloomberg’s unique business model and corporate culture into a larger organization would be exceedingly difficult.   An IPO seems unlikely. A spokesperson could not immediately be reached for comment.

2. Koch Industries Inc.,  which does everything from refine chemicals to make consumer products such as Brawny paper towels, clearly likes the flexibility that comes with being a  private company.  In 2007,  CEO Charles Koch told Amity  Shales of the Council on Foreign Relations that he found quarterly earnings to be “pernicious.” As Shales wrote:

He said the old truism still held: If you, as a chief executive, obsess about delivering those “ever-increasing and predictable quarterly earnings, you are going to sacrifice long- term value.” He says only companies whose bosses the markets trust – such as Warren Buffett at Berkshire Hathaway Inc. – can focus on multiyear investments. In doing so, Buffett, the Sage of Omaha, has made a public company seem as if it is private.

The Kochs are savvy business people who are also huge backers of conservative political causes. They also very successful.  Revenue at the Kansas-based company was $100 billion last year, according to Forbes.   Koch was not immediately available for comment.

3. Chick fil-A offers something that many fast food customers never get — service.   Workers are unfailingly polite and will even help customers carry their food to their tables.   Later, they even go around to clean up trash and offer free soda refills.   This attention to detail has paid off.     Chick-fil-A, which owns more than 1,500 restaurants in 39 states, has posted 43 straight annual sales increases.  Sales hit $3.58 billion in 2010 and rose 5.62% on a same-store basis, surpassing McDonald’s which rose 5%.  What makes these figures even more impressive is that the chain is closed on Sunday.   The family of founder S. Truett Cathy likes that Chick-fil-A is a family business and has vowed never to sell, a spokeswoman says.

4. TV pitchman Jim Perdue is the third generation of his family to run Perdue Food Products.  The food and agribusiness firm generates more than $4.6 billion in annual sales and is the third-largest poultry producer in the United States.    Clearly, the Salisbury, Maryland firm, which has ruffled the feathers of environmentalists and animal rights activists takes pride is being “family run.” In fact, the corporate headquarters is across the street from the original Perdue family farm.  That makes an IPO or sale seem unlikely. A spokesperson couldn’t be reached for comment.

5. Cargill generated more than $109 billion in revenue last year, the most of any private company, according to Forbes.  Cargill was founded at the end of the Civil War by William Wallace Cargill and his descendants have controlled the company ever since then.   It probably too sees no reason to go public more than 140 years later, as the Minneapolis Star Tribune explained in January:

When the late Margaret Cargill’s charitable trusts wanted to sell off their company stock to free up billions of dollars for philanthropy, their representatives suggested a typical approach for a major corporation — a public stock offering.

But Cargill isn’t a typical major corporation.

The proposal went nowhere with the roughly 100 descendants of the company’s early leaders who control the Minnetonka-based agribusiness behemoth. And the complex deal that ultimately emerged — selling Cargill’s $20 billion-plus stake in fertilizer giant Mosaic Co. — underscored their determination to to keep Cargill private, immune to the whims and scrutiny of Wall Street.

An IPO or a sale seems as unlikely as ever.  Cargill spokeswoman Lisa Clemens told 24/7 Wall St.  that the firm has no plans to go public.  “Through the years, our family shareholders have supported the benefits of private, patient capital,” she says in an email. “They continue to express support for private ownership.”

6. Bechtel Corp.  , the world’s largest construction and engineering firm,, takes pride in being a family run business.  Its recent history, though,  has been rough. “In the late 1990s, Bechtel, under the direction of its fourth-generation family scion, CEO and chairman Riley Bechtel, began pumping nearly $1 billion into a series of disastrously timed investments in everything from e-commerce plays to telecom start-ups to power plants,” according to a 2004 story in Business 2.0.  Since its founding in 1898, four generations of Bechtels have lead company through 23,000 projects in 140 nations and seven continents including the Hoover Dam.  Kuwait Oil Fires and the Channel Tunnel, and given the unpredictability of the construction business, it would make a poor candidate to go public. Wall Street likes predictable earnings.     Its revenue in 2010 was $27.9 billion, down from $30.8 billion in 2009.  Like the Kochs, the Bechtel’s are known for their ties to conservative political causes.  Bechtel could not be reached for comment.

–Jonathan Berr

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