diff --git a/esm/models/esmfold2/processor.py b/esm/models/esmfold2/processor.py
index 9914a55a..21f89d58 100644
--- a/esm/models/esmfold2/processor.py
+++ b/esm/models/esmfold2/processor.py
@@ -339,7 +339,7 @@ def fold(
         lm_mask_pct: float | None = None,
         early_exit: bool = False,
         lm_dropout: float | None = 0.3,
-        msa_max_depth: int = 1024,
+        msa_max_depth: int | None = 1024,
         msa_column_mask_rate: float = 0.1,
         complex_id: str = "pred",
     ) -> MolecularComplexResult | list[MolecularComplexResult]:
@@ -364,9 +364,11 @@ def fold(
             LM-embedding dropout for this fold (fresh mask per loop → diverse
             ensemble on repeated folds). Defaults to ``0.3`` (paper folding-eval
             value); ``0``/``None`` disables.
-        msa_max_depth : int
+        msa_max_depth : int, optional
             Maximum number of MSA rows kept per loop (row subsampling
-            is drawn fresh per loop). Only affects inputs that carry an MSA.
+            is drawn fresh per loop). When ``None``, MSA row subsampling is
+            disabled and the full MSA depth is used. Only affects inputs that
+            carry an MSA.
         msa_column_mask_rate : float
             Fraction of MSA columns masked once before the loop
             (shared across loops). Only affects inputs that carry an MSA.
@@ -403,6 +405,8 @@ def fold(
                         early_exit=early_exit,
                         msa_max_depth=msa_max_depth,
                         msa_column_mask_rate=msa_column_mask_rate,
+                        # A null depth means "use the full MSA" => no subsampling.
+                        msa_subsample_at_inference=msa_max_depth is not None,
                         **sampler_kwargs,
                     )