Previous research showed that being mimicked leads people to act prosocial towards the mimicker, because mimickers are perceived as warm. However, most studies have focused primarily on interactions among dyads, ignoring the role of third-party observers. To address this gap, we conducted six preregistered experiments (total N = 1,629) in which we tested how third-party observers perceive individuals who are mimicked (i.e., mimickees) and individuals who mimic others (i.e., mimickers) using the Big Two framework. Results show that mimickees are perceived as more competent (but not warm), which leads mimickees (but not mimickers) to receive more donations. This effect is particularly pronounced when mimickers respond with the exact same movements, rather than when they respond with different movements. This indicates that it is not merely responding to others, but the actual imitation of movements that increases perceived agency and as a consequence donations. The results challenge the generalizability of previous theories on the effects of being mimicked.