Washington ? For one day at least, a Supreme Court case came down to the justices’ investment ideas, not their legal philosophies.

The stock holdings of three justices, and the job of another’s son, kept the court on Monday from even considering getting involved in a dispute pitting some of the nation’s largest companies against victims of South Africa’s former apartheid government.

The result was that a lawsuit will go forward accusing dozens of corporations of violating international law by assisting the old government. The companies and the Bush administration had asked the court to intervene, arguing that the lawsuit was damaging international relations, threatening to hurt South Africa’s economic development and punishing the companies using a fuzzy legal concept.

It appeared to be the first time in at least a quarter-century that the justices’ financial holdings prevented them from taking a case.

Four of the nine justices sat out the court’s consideration of the case. Federal law calls for at least six to hear any case.

Short of the required number, the court took the only path available to it and upheld an appeals court ruling allowing the lawsuit to proceed.

Chief Justice John Roberts and Justices Samuel Alito, Stephen Breyer and Anthony Kennedy provided no explanation for their decision not to take part in the case.

But those justices have ties to Bank of America Corp., Bristol-Myers Squibb Co., Colgate-Palmolive Co., Credit Suisse, Exxon Mobil Corp., Hewlett-Packard Co., IBM and Nestle SA, among nearly three dozen companies that asked the high court to step in.

Roberts, Alito and Breyer have investment interests among the companies, while Kennedy ‘s son, Gregory, is a managing director at Credit Suisse.

New York University law professor Stephen Gillers, an expert on judicial ethics, said he expects this issue to arise from time to time. “Whether it’s family relationships or wealth, this is going to happen,” Gillers said. “It hasn’t reached the point where we need to do something.”