Ratings agency Standard & Poor's, a unit of McGraw-Hill (NYSE: MHP), has once again thrust itself into the spotlight with its downgrade of Google (Nasdaq: GOOG).

Just seven business days after S&P downgraded the credit rating of the United States because of the contentious debt-ceiling debate, it reversed its "buy" rating of Google to "sell" because of Google's decision to buy Motorola Mobility (NYSE: MMI) for $12.5 billion.

Patents pending
Many observers believe that Google's main reason for buying Motorola is to acquire its treasure trove of patents. Patent hording has become a big -- and controversial -- topic lately, and Google may have purchased Motorola mainly as patent-lawsuit protection.

RPX (Nasdaq: RPXC), for example, is a company that provides what it calls "patent risk solutions." The company scoops up patents and then charges companies a fee to avoid litigation. If a company can afford the fees, it's just one cost of doing business. To a company that can't afford them, it could mean the cost of going out of business.

RPX's website informs us: "Patent litigation used to be a form of legal redress. Today it is a business model." Some people may call that a form of insurance; others may call it a form of racketeering.

A recent "This American Life" podcast chronicles the effects that so-called "patent trolls" can have on tech companies -- from the smallest to the largest.

Meanwhile, back at the ranch …
Google had already failed in its bid for Nortel Networks' wireless patents earlier this year, and if the rumors were true that Microsoft (Nasdaq: MSFT) was also in talks with Motorola, then Google may have felt that it had to make a preemptive, if somewhat desperate , strike.

The sky is not falling yet, and I think it's a bit early for S&P to be slamming Google; that rating reversal is a bit drastic. Why didn't S&P just issue a "hold" recommendation and take a wait-and-see posture? Does it truly believe that acquiring Motorola will send Google to its doom? Or has S&P just gotten used to the limelight and is not ready to give it up?

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