This column was originally published on RealMoney on Nov. 18 at 12:44 p.m. EST. It's being republished as a bonus for TheStreet.com readers.

Investors love to see insider buying in the stocks of companies they own and abhor insider selling. But it turns out that selling in one group of stocks -- the job search and recruitment companies -- may actually serve in a perverse way as a positive signal, according to the results of new research from Thomson Financial.

The Thomson study uncovered an intriguing link between labor market trends and insider selling at job search companies like Robert Half International ( RHI) and Administaff ( ASF). Whenever selling at these kinds of companies hits extreme highs, overall U.S. job growth increases on average, over the next year or more.

The study, called "Insiders Foresee Changes in Unemployment Rate," found that when selling increases enough, unemployment falls over the next 12 to 24 months by anywhere from 3.2% to 5.7%.

So what does insider selling in this group say now about future employment trends? Insiders are selling at near-extreme levels once again -- suggesting further strength ahead for both the job market and recruitment stocks, if history is a good guide.

Robert Half International insiders, for example, dumped more than $41 million worth of stock since late July. At Administaff, insiders sold a hefty $13 million since the end of August. And at Kelly Services ( KELYA), top execs sold more than $5 million worth of stock since the end of July.

All of this selling, however, makes you wonder: Exactly why would insiders be dumping such large positions if future labor market trends are about to make their business even stronger?

Thomson's Mark LoPresti, the author of the study, takes the unconventional view that strong labor markets are actually bad for job search companies. He reasons that tight labor markets make it easier for people to find work -- so they sidestep the job search companies.

To explain the conundrum, however, I'd start with the more conventional view of analysts that recruitment companies actually do best as the economy moves out of recession and grows. During these times, businesses have a harder time finding workers. So they turn to job search firms for help finding all kinds of workers -- from temporary help to executive talent.

Thomson's study may have simply discovered that insiders sell when their stocks are moving up because job markets and the economy are stronger. But the study results have predictive powers, nevertheless, for a simple reason: The key is that insiders typically act too early -- way ahead of the trends they foresee. So it makes sense employment markets would continue to strengthen after they sell.

For investors, here's the takeaway: The current selling means more job growth ahead is likely, so job search stocks are still attractive even though many are selling near 52-week highs.

As with any group, however, you have to be selective and keep an eye on valuations. CIBC World Markets analyst Thatcher Thompson, for example, likes Robert Half International and Resources Connection ( RECN). They both help find professionals in areas like auditing, accounting, finance and risk management.

But at $37.60 per share, Robert Half trades near the analyst's 12- to 18-month price target of $38. In contrast, at $28.90, Resources Connection trades well below his $38 price target. So Resources Connection looks like the better buy. Thompson thinks Resources Connection will continue to benefit as audit firms have to shed nonaudit work for clients, thanks to Sarbanes Oxley.

Two other stocks in the group that seem attractive are Labor Ready ( LRW) and Heidrick & Struggles International ( HSII). At $22.80, Labor Ready trades for about 17 times next year's earnings, below the group average of 19 times forward earnings. But James Janesky of Ryan Beck & Co. thinks Labor Ready will do better than expected next year, take on a premium to the group, and hit his $30 price target. At $33, Heidrick & Struggles trades for 17 times next year's earnings, but even less if you factor in around $7 per share in cash. Wachovia's Mark Marcon believes the stock could trade as high as $39 in the next 18 months.

Administaff, in contrast, looks fully valued so it would pay to wait for a pullback, suggests JPM Securities analyst James Wilson. At $42, the stock trades for 30.4 times next year's earnings.

One job search company sticks out like an Ivy League resume -- because an insider is buying while overall selling in the group is heavy. At CDI ( CDI), finance chief Mark Kerschner bought $135,000 worth of his company's stock around $27 earlier this month. Hey, maybe betting that a recent big contract with IBM ( IBM) will help bolster growth next year.

P.S. from TheStreet.com Editor-in-Chief, Dave Morrow:
It's always been my opinion that it pays to have more -- not fewer -- expert market views and analyses when you're making investing or trading decisions. That's why I recommend you take advantage of our free trial offer to TheStreet.com RealMoney premium Web site, where you'll get in-depth commentary and money-making strategies from over 50 Wall Street pros, including Jim Cramer. Take my advice -- try it now.

Michael Brush assisted in the research of this article.

Jon Markman, writer of TheStreet.com Value Investor, is the senior investment strategist and portfolio manager at Greenbook Investment Management, a division of Greenbook Financial Services. Separately, he is publisher of StockTactics Advisor, an independent weekly investment research service. While Markman cannot provide personalized investment advice or recommendations, he appreciates your feedback; click here to send him an email.

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