diff --git a/dsv4/ops/gemm_runner.py b/dsv4/ops/gemm_runner.py
index 2b4f615c..5d0501e7 100644
--- a/dsv4/ops/gemm_runner.py
+++ b/dsv4/ops/gemm_runner.py
@@ -416,6 +416,7 @@ def run_fused_swiglu_grouped_gemm(
     swiglu_limit=0.0,
     mma_tiler_mn=(128, 128),
     cluster_shape_mn=(1, 1),
+    out=None,       # pre-allocated output buffer for CUDA graph capture
 ):
     """Run the fused SwiGLU NVFP4 scaled grouped GEMM.