Human capital as an intellectual capital dimension in SME open innovation: servant leadership, employee-oriented CSR and organizational support

Purpose This study examines how human capital (HC), as one dimension of intellectual capital (IC), is associated with inbound open innovation (IOI) in small and medium-sized enterprises (SMEs). Corresponding outbound open innovation (OOI) paths are retained as exploratory extensions. The study also considers servant leadership (SL), corporate social responsibility to employees (CSRE), and managerially assessed organizational support (POS). Design/methodology/approach Survey data from 286 Vietnamese SMEs were analyzed using partial least squares structural equation modelling with 5,000 bootstrap samples. Predictive assessment combined blindfolding, PLSpredict, and supplementary artificial neural network (ANN) models. Findings SL is positively associated with CSRE and HC, while CSRE and HC are positively associated with IOI. The corresponding direct paths to OOI are not significant. HC provides a significant complementary indirect pathway between CSRE and IOI. An additional model shows that SL has no significant direct association with either IOI or OOI. The SL-IOI relationship is consistent with indirect-only mediation, whereas no specific indirect pathway to OOI is significant. POS strengthens the CSRE-HC and HC-IOI associations. Predictive performance is stronger for CSRE and HC, limited for IOI, and negligible for OOI. ANN models do not outperform matched linear benchmarks. Research limitations/implications The cross-sectional, single-informant design limits temporal and causal interpretation. Future studies should use longitudinal, multi-source designs and incorporate structural and relational capital, particularly when explaining OOI. Practical implications SMEs should strengthen employee knowledge and routines for acquiring and integrating external knowledge. For OOI, HC should be complemented by knowledge codification, intellectual property protection, commercialization routines, and trusted external relationships. Originality/value Rather than treating HC as an exogenous innovation resource, the study examines its organizational antecedents by positioning servant leadership and employee-oriented corporate social responsibility upstream of HC. The resulting SL-CSRE-HC pathway links leadership and responsible employee practices to the human-capital base associated with inbound open innovation, while the corresponding exploratory direct paths to OOI are not statistically significant in this sample.