Volume 5, Issue 3

Background. Family firms are often described as reluctant to share knowledge beyond the family, yet many rely on suppliers, customers and universities to innovate. Research on open innovation in family firms has grown quickly but remains fragmented and apparently contradictory. Objective. This review synthesized evidence on the open innovation practices of family firms, their antecedents and their outcomes. Methods. Following PRISMA 2020 guidance, we searched Scopus, Web of Science Core Collection and Business Source Complete in January 2026 for peer-reviewed empirical studies published from 2006 to 2025, supplemented by citation tracking. Two reviewers independently screened records, extracted data and appraised study quality, and findings were integrated through thematic synthesis. Results. Of 1,486 records identified, 66 studies met the inclusion criteria; most were quantitative (66.7%) and conducted in Europe (57.6%). Family firms engaged less often than nonfamily firms in outbound practices such as licensing-out and searched more narrowly for external knowledge, but they formed deeper and more durable partnerships. Socioemotional wealth priorities restrained openness, whereas later-generation leadership, nonfamily managers and independent directors increased it. Of 19 studies examining outcomes, 15 reported that openness was associated with higher innovation output, often more strongly in family firms with high absorptive capacity. Conclusions. Family firms practice a selective, relationship-based form of open innovation rather than simply less of it. Future research should use longitudinal designs, distinguish inbound, outbound and coupled practices and include more firms from Asia, Africa and Latin America.