diff --git a/.github/workflows/build-statsmodels.yml b/.github/workflows/build-statsmodels.yml
index 4a34640650..633ca97126 100644
--- a/.github/workflows/build-statsmodels.yml
+++ b/.github/workflows/build-statsmodels.yml
@@ -82,9 +82,11 @@ jobs:
           CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
           # PIP_ONLY_BINARY keeps numpy/scipy/pandas on our registry's riscv64 wheels
           # instead of source-building the newer releases PyPI offers; setuptools_scm
-          # is pinned because the shallow tag checkout carries no version history.
+          # is pinned because the patched tree is dirty at the tag. statsmodels'
+          # meson.build calls setuptools_scm.get_version() directly with no dist_name,
+          # so only the unscoped var (not _FOR_STATSMODELS) is honored.
           CIBW_ENVIRONMENT: >-
-            SETUPTOOLS_SCM_PRETEND_VERSION_FOR_STATSMODELS=${{ env.STATSMODELS_VERSION }}
+            SETUPTOOLS_SCM_PRETEND_VERSION=${{ env.STATSMODELS_VERSION }}
             PIP_EXTRA_INDEX_URL=https://pypi.riseproject.dev/simple/
             PIP_ONLY_BINARY=numpy,scipy,pandas
             MKL_NUM_THREADS=1
diff --git a/docs/packages/statsmodels.yaml b/docs/packages/statsmodels.yaml
index 4d7733b3a9..90260ba840 100644
--- a/docs/packages/statsmodels.yaml
+++ b/docs/packages/statsmodels.yaml
@@ -12,3 +12,4 @@ versions:
   - filename: statsmodels-0.14.6-cp313-cp313-manylinux_2_31_riscv64.manylinux_2_39_riscv64.whl
     sha256: d19c3b8befc7037d9fa9136b12c32b696417a4ea3e93c86632ddd0acd36932c8
     requires-python: '>=3.9'
+- version: 0.15.0
diff --git a/patches/statsmodels/0.15.0/0001-BUG-use-eigh-for-the-symmetric-matrix-in-_design_kno.patch b/patches/statsmodels/0.15.0/0001-BUG-use-eigh-for-the-symmetric-matrix-in-_design_kno.patch
new file mode 100644
index 0000000000..20e656af02
--- /dev/null
+++ b/patches/statsmodels/0.15.0/0001-BUG-use-eigh-for-the-symmetric-matrix-in-_design_kno.patch
@@ -0,0 +1,41 @@
+From 31c88b884dc8121d00daf79518915788290cc607 Mon Sep 17 00:00:00 2001
+From: Ludovic Henry <git@ludovic.dev>
+Date: Fri, 18 Sep 2026 06:38:25 +0000
+Subject: [PATCH] BUG: use eigh for the symmetric matrix in
+ _design_knockoff_equi
+
+`xcov` is `exog.T @ exog`, so it is symmetric positive semi-definite and its
+eigenvalues are real. `np.linalg.eig` calls LAPACK's general `dgeev`, which
+returns a complex array whenever rounding leaves any imaginary part non-zero
+-- what happens depends on the BLAS kernels, and OpenBLAS's riscv64_generic
+ones do it for these matrices where the x86_64 and aarch64 ones do not.
+`evmin` is then complex, `min(2 * evmin, 1)` picks it over the real 1, and
+`_get_knmat` dies on the first in-place multiply:
+
+    ash *= -np.outer(sl, sl)
+    numpy._core._exceptions._UFuncOutputCastingError: Cannot cast ufunc
+    'multiply' output from dtype('complex128') to dtype('float64') with
+    casting rule 'same_kind'
+
+`eigh` uses `dsyevd`, is real by construction on every platform, and agrees
+with `eig` to 3e-15 on the same inputs. This is 13 failures in
+stats/tests/test_knockoff.py on riscv64 -- every `equi` parametrisation.
+
+Upstream-Status: To upstream [not yet submitted; pending review of the riscv64 port that found it]
+---
+ statsmodels/stats/_knockoff.py | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/statsmodels/stats/_knockoff.py b/statsmodels/stats/_knockoff.py
+index cbbbe9f04..a2de99a2e 100644
+--- a/statsmodels/stats/_knockoff.py
++++ b/statsmodels/stats/_knockoff.py
+@@ -238,7 +238,7 @@ def _design_knockoff_equi(exog, rng):
+     exog = exog / xnm
+ 
+     xcov = np.dot(exog.T, exog)
+-    ev, _ = np.linalg.eig(xcov)
++    ev, _ = np.linalg.eigh(xcov)
+ 
+     if np.iscomplexobj(ev):
+         if np.all(ev.imag == 0):