diff --git a/dev_tools/requirements/envs/dev.env.txt b/dev_tools/requirements/envs/dev.env.txt
index 9d664981..90abb769 100644
--- a/dev_tools/requirements/envs/dev.env.txt
+++ b/dev_tools/requirements/envs/dev.env.txt
@@ -56,9 +56,9 @@ iniconfig==2.0.0
     # via pytest
 isort==5.13.2
     # via pylint
-jax==0.4.23
+jax==0.4.31
     # via -r deps/resource_estimates_runtime.txt
-jaxlib==0.4.23
+jaxlib==0.4.31
     # via -r deps/resource_estimates_runtime.txt
 jsonschema==4.21.0
     # via nbformat
diff --git a/dev_tools/requirements/envs/pytest-extra.env.txt b/dev_tools/requirements/envs/pytest-extra.env.txt
index c361de5a..8f424118 100644
--- a/dev_tools/requirements/envs/pytest-extra.env.txt
+++ b/dev_tools/requirements/envs/pytest-extra.env.txt
@@ -74,11 +74,11 @@ iniconfig==2.0.0
     # via
     #   -c envs/dev.env.txt
     #   pytest
-jax==0.4.23
+jax==0.4.31
     # via
     #   -c envs/dev.env.txt
     #   -r deps/resource_estimates_runtime.txt
-jaxlib==0.4.23
+jaxlib==0.4.31
     # via
     #   -c envs/dev.env.txt
     #   -r deps/resource_estimates_runtime.txt
diff --git a/src/openfermion/resource_estimates/pbc/thc/factorizations/thc_jax.py b/src/openfermion/resource_estimates/pbc/thc/factorizations/thc_jax.py
index 6c86bbef..45f9ce13 100644
--- a/src/openfermion/resource_estimates/pbc/thc/factorizations/thc_jax.py
+++ b/src/openfermion/resource_estimates/pbc/thc/factorizations/thc_jax.py
@@ -35,11 +35,10 @@
 from pyscf.pbc import scf
 from scipy.optimize import minimize
 
-from jax.config import config
+import jax
 
-config.update("jax_enable_x64", True)
+jax.config.update("jax_enable_x64", True)
 
-import jax
 import jax.numpy as jnp
 import jax.typing as jnpt
 
diff --git a/src/openfermion/resource_estimates/thc/factorize_thc.py b/src/openfermion/resource_estimates/thc/factorize_thc.py
index 29838c7d..86c9c9ab 100644
--- a/src/openfermion/resource_estimates/thc/factorize_thc.py
+++ b/src/openfermion/resource_estimates/thc/factorize_thc.py
@@ -18,6 +18,7 @@ def thc_via_cp3(
     bfgs_maxiter=5000,
     random_start_thc=True,
     verify=False,
+    penalty_param=None,
 ):
     """
     THC-CP3 performs an SVD decomposition of the eri matrix followed by a CP
@@ -36,6 +37,7 @@ def thc_via_cp3(
         random_start_thc - Perform random start for CP3.
                            If false perform HOSVD start.
         verify - check eri properties. Default is False
+        penalty_param - penalty parameter for L2 regularization. Default is None.
 
     returns:
         eri_thc - (N x N x N x N) reconstructed ERIs from THC factorization
@@ -115,7 +117,9 @@ def thc_via_cp3(
     if perform_bfgs_opt:
         x = np.hstack((thc_leaf.ravel(), thc_central.ravel()))
         # lbfgs_start_time = time.time()
-        x = lbfgsb_opt_thc_l2reg(eri_full, nthc, initial_guess=x, maxiter=bfgs_maxiter)
+        x = lbfgsb_opt_thc_l2reg(
+            eri_full, nthc, initial_guess=x, maxiter=bfgs_maxiter, penalty_param=penalty_param
+        )
         # lbfgs_calc_time = time.time() - lbfgs_start_time
         thc_leaf = x[: norb * nthc].reshape(nthc, norb)  # leaf tensor  nthc x norb
         thc_central = x[norb * nthc : norb * nthc + nthc * nthc].reshape(
diff --git a/src/openfermion/resource_estimates/thc/utils/thc_factorization.py b/src/openfermion/resource_estimates/thc/utils/thc_factorization.py
index 922b6317..16f7ae6a 100644
--- a/src/openfermion/resource_estimates/thc/utils/thc_factorization.py
+++ b/src/openfermion/resource_estimates/thc/utils/thc_factorization.py
@@ -1,4 +1,5 @@
 # coverage:ignore
+# pylint: disable=wrong-import-position
 import os
 from uuid import uuid4
 import h5py
@@ -6,9 +7,12 @@
 import numpy.random
 import numpy.linalg
 from scipy.optimize import minimize
+
 import jax
+
+jax.config.update("jax_enable_x64", True)
+
 import jax.numpy as jnp
-from jax.config import config
 from jax import jit, grad
 from .adagrad import adagrad
 from .thc_objectives import (
@@ -22,7 +26,6 @@
 # set mkl thread count for numpy einsum/tensordot calls
 # leave one CPU un used  so we can still access this computer
 os.environ["MKL_NUM_THREADS"] = "{}".format(os.cpu_count() - 1)
-config.update("jax_enable_x64", True)
 
 
 class CallBackStore:
diff --git a/src/openfermion/resource_estimates/thc/utils/thc_objectives.py b/src/openfermion/resource_estimates/thc/utils/thc_objectives.py
index 3cbdd96a..366f25b2 100644
--- a/src/openfermion/resource_estimates/thc/utils/thc_objectives.py
+++ b/src/openfermion/resource_estimates/thc/utils/thc_objectives.py
@@ -1,9 +1,14 @@
 # coverage:ignore
+# pylint: disable=wrong-import-position
 import os
 from uuid import uuid4
 import scipy.optimize
+
+import jax
+
+jax.config.update("jax_enable_x64", True)
+
 import jax.numpy as jnp
-from jax.config import config
 from jax import jit, grad
 import h5py
 import numpy
@@ -15,7 +20,6 @@
 # set mkl thread count for numpy einsum/tensordot calls
 # leave one CPU un used  so we can still access this computer
 os.environ["MKL_NUM_THREADS"] = "{}".format(os.cpu_count() - 1)
-config.update("jax_enable_x64", True)
 
 
 def thc_objective_jax(xcur, norb, nthc, eri):