Every quarter, many money managers have to disclose what they've bought and sold, via "13F" filings. Their latest moves can shine a bright light on smart stock picks.

Today, let's look at investment advisory firm Douglass Winthrop Advisors. It’s of interest because it employs a Foolish "low-turnover, buy and hold strategy" -- and it has been served well by that, too. Since its inception roughly a decade ago, its equities investments have averaged annual gains of 8%, versus 6.8% for the S&P 500. Management noted in a recent letter to shareholders:

As committed long-term investors we keep our clients invested through good days and the inevitable bad ones. While this makes for some queasy moments, our clients understand that what really matters are long-term returns net of fees and taxes.

The company's reportable stock portfolio totaled about $700 million in value as of June 30, 2012.

Interesting developments
So what does Douglass Winthrop’s latest quarterly 13F filing tell us? Here are a few interesting details:

New holdings include Phillips 66 (NYSE: PSX), the recently spun-off downstream business of ConocoPhillips. It's the nation's largest independent oil refiner, and its stock recently hit a 52-week high, getting a boost from falling oil prices that swell its profit margins. It also paid its first dividend, yielding about 1.7%. Its stock is less of a bargain now, though, and its bears worry about competition and tight profit margins. Interested investors might want to wait for stronger profit margins or a lower entry price. Analysts at Citi recently downgraded it and other refiners on valuation concerns and the risk of a warm winter.

Among holdings in which Douglass Winthrop increased its stake was gas and surface-coating specialist Praxair (NYSE: PX). The company has a lot of debt, and recently issued $500 million more, though at a low coupon rate of 2.2%. On the plus side, its revenue and earnings have been growing at a double-digit clip over the past year or so. In a recent conference call, management mentioned currency exchange rates as hurting results. Management is also waiting for the European and Brazilian markets to turn around. Praxair recently signed a 15-year agreement with Honeywell to buy carbon dioxide. It will process it into products for the beverage industry, and for freezing food.

Douglass Winthrop reduced its stake in several companies, including Sirius XM Radio (Nasdaq: SIRI). Some worry that streaming music competition will sink Sirius, but Sirius has been growing its subscribership and monthly price despite that. A serious issue is the company's debt load, but if it can grow its cash flow more, that will become less of a worry. Meanwhile, Liberty Media has been approaching majority control of the company, and some think CEO Mel Karmazin will depart in the near future. 

Finally, Douglass Winthrop unloaded several companies, such as New York Community Bancorp (NYSE: NYB) and Cliffs Natural Resources (NYSE: CLF). New York Community Bancorp does have an appealing 7.2% dividend yield and a seemingly low valuation. The company isn’t expected to grow very rapidly, but it does seem to offer a sizable upside. Bears don’t like its high cost of funds relative to peers, and some are skeptical about its growth-via-acquisition strategy.

Cliffs Natural Resources, meanwhile, recently yielded 5.9%. The stock has fallen sharply over the past year, largely due to a struggling coal industry. Still, bulls like its prospects, especially once the auto industry and others recover more strongly, as Cliff's metallurgical coal is used in making steel. Some recent good news is China’s plan to spend some $156 billion beefing up its infrastructure, which will certainly spur demand for coal. Cliffs seems attractively priced, as well.

We should never blindly copy any investor's moves, no matter how talented the investor. But it can be useful to keep an eye on what smart folks are doing, and 13-F forms can be great places to find intriguing candidates for our portfolios.

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