Firm Adopts Shareholder Rights Plan : Management: Bergen Brunswig, supplier of pharmaceuticals, acts to discourage takeover attempts.

Drug distributor Bergen Brunswig Corp., preparing to streamline its stock ownership and voting rights, said Wednesday that it has adopted a shareholders’ rights plan to ward off hostile parties who might think of trying to take over the company.

The plan, a common corporate provision that most major companies already have, was part of Bergen’s decision in 1989 to abolish its dual system of stock ownership and voting that gave the Martini brothers, the chief operators, effective control of the company.

No one, however, is trying to take over the nation’s largest supplier of pharmaceuticals to hospitals and managed care facilities, corporate officials and industry analysts said.

“I can’t imagine somebody wanting to take over a business like this with such a small profit margin,” said Sally L. Schaadt, an analyst for Fourteen Research in New York. “Even on its best days, the company does not have more than a 2% profit margin, and they have to work very hard and be a technological superstar to get that.”

The company’s announcement didn’t surprise Wall Street.

“I’ve talked to a couple of institutional investors, and no one reading the press release sees it as a big surprise,” said Lawrence C. Marsh, an industry analyst at Wheat First Butcher & Singer in Richmond, Va. “They read it almost as a non-event.”

In trading on the New York Stock Exchange, Bergen’s stock price fell 12.5 cents a share to close at $19.125.

Brothers Emil and Robert Martini had controlled the company through their ownership of the Class B stock, which was entitled to elect six of the board’s 11 directors. But in 1989, the Martinis agreed to give up their Class B stock and to convert it by Feb. 24, 1994.

Emil died two years ago, and his estate has a minor interest in the company. Robert is the company’s chairman and owns nearly all the Class B stock. He will have a 7.75% stake in the company after those shares are converted.

As part of their 1989 changes, directors agreed that a shareholders’ rights plan would be put into place by Feb. 24 at the latest, said Michael Sawdei, the company’s legal counsel.

The company views Wednesday’s announcement as a reminder that what was contemplated previously has become effective.

“I don’t think anyone following us is surprised by this,” said Karen Wiley, a Bergen spokeswoman.

Marsh and Schaadt said that Bergen’s operating income, which doesn’t take into account the $30-million cost of corporate restructuring last year, has been flat because drug prices haven’t risen as fast as they had in the past. The company earned $26 million in its latest fiscal year, which ended Aug. 31, on revenue of $6.8 billion.