Business Notes WALL STREET

On Wall Street, anti-takeover ploys are becoming as pervasive as red suspenders. Last week four blue-chip companies, including Dow Chemical and ^ American Express, unveiled a new financial product that could become a deterrent to corporate raiders. The firms will buy back as much as $5.6 billion worth of their shares with so-called unbundled stock units: packages that include a bond and two new types of securities. Partly because the new packages will allow the companies to pay less in taxes, investors might bid up the price of the new units. Raiders, Wall Streeters believe, might resist paying such a premium, thus foiling takeover bids.

But the new-age stock could inspire little more than a yawn. Investors may have trouble determining a fair value for the package, which is far more complex than a share of common stock. Says one financier: "This is an instance of financial engineering going too far."