Laderman's 1976 construction gives a 23-multiplication algorithm for 3×3 matrix multiplication over the reals. The best-known lower bound is 19 (Bläser). The gap has stood for five decades. Closing even one multiplication — 22 or fewer — would be the first improvement on one of the oldest open records in bilinear complexity theory.

**Verification.** Identical structure to AX-00011 at 9×9×9 tensor scale: 22 rank-one triples (u, v, w) ∈ ℝ^9, sum must equal the 3×3 mat-mul tensor. Exact checking for rational submissions; numerical tolerance for floating-point.

**State.** Open. 50-year standing record.