Brussels — American and European companies that sell products in developing nations have recently begun to lobby for protection of their technological patents.
The efforts are directed at their government representatives, who will meet in Geneva this fall for a United Nations-sponsored revision of an international treaty on patents, or what is termed ''intellectual'' or ''industrial'' property.
Like other clashes between poor and rich nations, such as the Law of the Sea treaty proposal, the negotiating atmosphere is tense. The financial stakes are extremely high.
Companies that rely on new research ideas from their scientists are intent on reversing the position of Western European and Canadian governments, which now support demands by the third world to ease access to new technology. The United States, in backing the interests of private industry, is largely isolated in the talks.
Developing countries intent on industrialization are seeking to whittle down the dominance of foreign, industrialized companies in their countries. The Organization for Economic Cooperation and Development in Paris indicates that its 24 industrialized members' exports for heavy and manufactured goods to the third world grew from about $51 billion a year in 1970 to close to $305 million in 1979.
One change sought by the third world in the treaty is the elimination of an invention's patent protection if it is not used by the patentholder after five years. Industrial opponents say this period of time is generally insufficient to launch a manufacturing and marketing operation in a given country. They argue that the demand would amount to expropriation of property by the developing countries.
Nevertheless, at a preliminary negotiating session in Nairobi, Kenya, last year, nearly all 68 participating countries except the United States leaned toward the third world arguments.
The difference between the views of industry representatives and government positions was apparent at a meeting in Brussels. One European participant noted: ''We want to bridge the gap between the European and American government positions. The US government view represents its industrial interests, but the European positions don't.''
The participants' general view was that the proposals agreed to in Nairobi and scheduled for final adoption in Geneva would threaten the transfer of technology to developing nations by making companies more cautious in their investments.
The Brussels strategy session was attended by representatives of companies such as Bell Laboratories, FMC Corporation, Polaroid, Procter & Gamble, and the US-based Pharmaceutical Manufacturers Association. It was conducted by the Common Market's industrial lobbying organization, the Union of Industries of the European Community.