Watch for the Third Rail at Corning

This article first appeared May 14 on RealMoney. To read Arne's commentary regularly, please click here for a free trial.

The game is up. The buildout is over. Shareholders of Corning (GLW Quote) are in for a rude awakening. This $7 billion market-cap company could very well lose much of its equity value in the near future.

As a leading provider of optical fiber and cable, Corning is analogous to the rail manufacturers of the mid-1800s. With the advent of the railroad, the stock market was in a speculative frenzy back then, just as it was during the Internet craze of the 1990s. Of course, the market had justification: The railroad revolutionized business.

As those rail manufacturers soon learned, though, once the rail lines were built, the manufacturers became irrelevant. The owner of the railroad, the product distributors and consumers reaped the benefits of the railroad, not the rail manufacturer. ...