Relational individuation and no further first-person fact under perfect phenomenal duplication

Perfect phenomenal duplication invites a familiar thought: two experiences could match in every phenomenal and structural respect and yet still differ in a further first-person fact about which one is mine. Work on self-location and centered worlds explains why uncentered description can leave that question open, but it does not by itself decide whether the residual openness reflects an additional internal fact or merely multiple compatible centers. This paper argues that a restricted anti-haecceitist premise blocks the further-fact reading. Relational individuation (RI) says that once the phenomenal and structural profile of an occurrent experience is fixed, no further internal first-person fact remains that could privilege one perfect duplicate as uniquely mine. I specify the duplicated base, distinguish token multiplicity from presence-individuation and external indexing, and argue that centered-world formalisms are best treated as setup rather than solution. The result separates the existence of multiple experiential tokens from any further internal fact of exclusive first-person privilege. Perfect duplication does not itself reveal a hidden extra first-person fact; that reading requires a primitive asymmetry-maker not contained in the duplicated profile.