The authors clarify the behavioral traits of PLP (Partnership Loyalty Program) members before their trial purchase at the focal company. Specifically, they apply a zero-inflated negative binomial regression model using historical data of PLP members: purchase, marketing reaction, and reward program usage. There are two contributions to their research. First, they clarify the behavioral traits of PLP members at other coalitional companies before the trial purchase at the focal company, which cannot be captured by the loyalty program of a single company. Then, the behavioral traits of PLP members are captured from the three perspectives: purchasing behavior, marketing reaction, and reward acquisition/redemption behavior. These results induce discussions on the effectiveness of PLP from the perspective of sharing and utilizing behavioral information of PLP members among coalitional companies.