A very large company in a field with high technological demands--IBM, for example-- has the resources to run a sophisticated research program. But what about the companies that aren't quite so large? Last year a dozen of them set up a joint venture called MCC, the Microelectronics and Computer Technology Coroporation, to carry on research and development for all of them. But it may expose them to antitrust litigation.

Legal scholars say that this kind of joint venture has almost never been found in violation. But corporate lawyers are uneasy. The law is imprecise, and antitrust cases are notoriously unpredictable. The risks are increased by the rapidly growing practice of plaintiffs' lawyers' organizing civil antitrust suits in pursuit of the triple damages and fees that the law provides. Last week a federal judge awarded fees totaling $40.7 million to the plaintiffs' lawyers in a price-fixing case involving cardboard boxes; that worked out to $352 an hour for the lawyers. Where rewards are high, litigation will increase.

The Justice Department said last December that it would not challenge the organization of MCC, but specifically would not provide advance approval of its activities. The head of MCC, Adm. Bobby R. Inman, said that he interpreted that position as "an amber light" to proceed cautiously--but he added, not entirely in jest, that his own lawyer had advised him not to get involved.

Much of American antitrust law is now obsolescent, and it regularly produces anomalies like this one. As computer technology accelerates, development costs are rapidly rising. The goal of the antitrust tradition is presumably to maintain competition by, among other things, encouraging the largest possible number of competitors. But if joint research ventures are legally risky, the alternative is the familiar succession of mergers and takeovers until only a few big companies remain.

President Reagan has now proposed legislation that would explicitly declare this kind of joint venture to be legal as long as it does not engage in price-fixing or suppression of innovation. With this bill, he makes a valuable contribution to companies' capacity to undertake research. It deserves prompt consideration by Congress.

The president's bill is also an answer to the industrial policy plans currently being floated. Industrial policy, as the term is currently being used here in Washington, carries unappealing connotations of subsidy and protection for declining industries. Mr. Reagan, in contrast, is offering help to those who are willing to use their own resources in the most useful of ways to help themselves.