Warren Buffett attracts a lot of attention. As the world's third-richest person and most celebrated investor, thousands try to glean what they can from his thinking processes and track his investments.

While we can't know for sure whether Buffett is about to buy Pfizer (NYSE: PFE) -- he hasn't specifically mentioned anything about it to me -- we can discover whether it's the sort of stock that might interest him. Answering that question could also inform whether it's a stock that should interest us.

In his most recent 10-K, Buffett lays out the qualities he looks for in an investment. In addition to adequate size, proven management, and a reasonable valuation, he demands:

  1. Consistent earnings power.
  2. Good returns on equity with limited or no debt.
  3. Management in place.
  4. Simple, non-techno mumbo jumbo businesses.

Does Pfizer meet Buffett's standards?

1. Earnings power
Buffett is famous for betting on a sure thing. For that reason, he likes to see companies with demonstrated earnings stability.

Let's examine Pfizer's earnings and free cash flow history:

Source: Capital IQ, a division of Standard & Poor's. Free cash flow is adjusted based on author's calculations.

Over the past five years, Pfizer has exhibited fairly consistent earnings.

2. Return on equity and debt
Return on equity is a great metric for measuring both management's effectiveness and the strength of a company's competitive advantage or disadvantage -- a classic Buffett consideration. When considering return on equity, it's important to make sure a company doesn't have an enormous debt burden, because that will skew your calculations and make the company look much more efficient than it actually is.

Since competitive strength is a comparison among peers, and various industries have different levels of profitability and require different levels of debt, it helps to use an industry context.

Company

Debt-to-Equity

Return on Equity (LTM)

Return on Equity
(5-Year Average)

Pfizer 46% 9% 12%
GlaxoSmithKline (NYSE: GSK) 153% 19% 49%
Mylan (Nasdaq: MYL) 142% 10% 7%
Bristol-Myers Squibb (NYSE: BMY) 34% 31% 26%

Source: Capital IQ, a division of Standard & Poor's.

Pfizer produces a fairly modest return on equity while employing moderate debt.

3. Management
CEO Ian Read has only been at the job since last December. He'd been at the company for several years prior to that, however.

4. Business
Diversified pharmaceuticals require constant research and development and pipeline difficulties are a threat, but the industry isn't particularly susceptible to wholesale technological disruption.

The Foolish conclusion
Regardless of whether Buffett would ever buy Pfizer, we've learned that, while it's generated fairly steady earnings over the past five years, the company doesn't particularly exhibit some of the other characteristics of a quintessential Buffett investment: high returns on equity with limited debt, tenured management.

If you'd like to stay up-to-speed on the top news and analysis on Pfizer or any other stock, simply click here to add it to your stock watchlist. If you don't have one yet, you can create a watchlist of your favorite stocks by clicking here.

Ilan Moscovitz doesn't own shares of any companies mentioned. The Motley Fool owns shares of GlaxoSmithKline. Motley Fool newsletter services have recommended buying shares of GlaxoSmithKline and Pfizer. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.