Do European Computer-Related Patents Increase Welfare?

When the home country introduces a patent law after the winner of the patent race is known, the country's welfare may rise only if the domestic firm wins. If the home country decides before the patent race ends, the welfare may be increased when the probability that the domestic firm wins is sufficiently large. In both cases, the conditions on the product market determine the welfare gain. However one may at least doubt whether those conditions are satisfied.