Social identity formation among Pride parade participants.

Introduction: This study examines the formation of social identity among Pride parade participants. Methods: Semi-structured interviews were conducted with 36 individuals who participated in Pride parades in Japan, including 24 identified as LGBT+, 9 as non-LGBT+, and 3 as unspecified. Data were analyzed using constructivist grounded theory. Findings: The process of social identity formation was categorized into four stages: (1) Belonging to the In-Group, (2) Behaving as an In-Group Member, (3) Recognizing One's Role within the In-Group, and (4) Universalizing the In-Group Identity. In the Belonging stage, participants perceived themselves as the in-group while positioning heteronormative society as the out-group. In the Behaving stage, shared practices such as carrying rainbow flags and chanting reinforced group solidarity. In the Recognizing stage, participants were differentiated into Core and Supporting roles, highlighting internal role differentiation. In the Universalizing stage, participants emphasized attitudinal differences between in-group and out-group while simultaneously expressing a goal of dissolving such boundaries. Discussion: These findings contribute to the application of social identity theory to Pride parade participation by demonstrating how collective action fosters shared identity formation among both LGBT+ and non-LGBT+ participants. The study also identifies a novel in-group-out-group configuration, conceptualized as the in-group within the out-group, and suggests the potential for integrating queer theory, particularly the concept of performativity, with social identity theory.