This study recognizes corporate mergers and acquisitions (M&A) strategy as a mechanism for acquiring external knowledge, and its primary purpose is to identify the specific conditions under which knowledge transfer from the acquired firm to the acquiring firm actively occurs. To this end, this study derived research hypotheses based on evolutionary economics, which emphasizes differences in capabilities among firms as the cause of their divergent evolutionary processes. To test the research hypotheses, M&A cases in the U.S. knowledge-based IT industry from 1981 to 1993 were used as the sample, and patent citation data from the U.S. Patent and Trademark Office were employed to measure the degree of knowledge transfer between the acquiring and acquired firms in each individual case. According to the statistical analysis results using negative binomial regression, first, the degree of the acquiring firm's technological path dependence had a positive effect on knowledge transfer up to a certain level, but beyond that level, excessive path dependence had a negative effect. Furthermore, differences in technological characteristics between the acquiring and acquired firms also had a positive effect on knowledge transfer up to a certain level, but high technological dissimilarity had a negative effect on knowledge transfer. Meanwhile, the pre-acquisition technological relatedness between the acquiring and acquired firms was found to have a positive effect on knowledge transfer.