Exploring the effect of line manager gratitude expression on employees’ knowledge hiding and unethical pro-supervisor behaviors

Purpose As a low-cost and effective way to maintain good interpersonal relations, gratitude expression has moved into the public glare of organizational management arena. Nonetheless, leader gratitude expression and its impact on employees’ behavior have received scarce attention. This study aims to elucidate the mechanisms underlying the effect of line manager gratitude expression on employees’ negative behaviors, that is, knowledge hiding and unethical pro-supervisor behavior (UPSB). Design/methodology/approach The authors conducted an experiment study and a field study. Study 1 invited full-time students from a Chinese university (n = 210) to participate a scenario-based experiment, then used SPSS 29.0 to conduct independent sample t-tests. Study 2 involved a time-lagged design with two waves of data collection over two months from employees in China (n = 550). The authors used Mplus 8.3 for confirmatory factor analysis and structural equation modeling to test the hypotheses. Findings An experimental study (Study 1) finds that line manager gratitude expression positively correlates with UPSB/rationalized hiding while negatively correlates with evasive hiding and playing dumb. Field study (Study 2) confirms the results and further finds that emotional expression authenticity moderates the relationship between line manager gratitude expression and employees’ negative behaviors (i.e. UPSB, evasive hiding and playing dumb). Originality/value Based on signaling theory, this study provides novel evidence on how line manager gratitude expression affects employee negative behaviors, thereby adding a new perspective to the literature on gratitude. The findings of this study contribute to the understanding of whether and when employees exhibit negative behaviors (i.e. UPSB and knowledge hiding) after they perceive line manager gratitude expression.