diff --git a/include/estimate_covariance/estimate_covariance.hpp b/include/estimate_covariance/estimate_covariance.hpp
index 4de5bd4..35da2a7 100644
--- a/include/estimate_covariance/estimate_covariance.hpp
+++ b/include/estimate_covariance/estimate_covariance.hpp
@@ -23,11 +23,6 @@ struct ResultOfMultiNdtCovarianceEstimation
 /** \brief Estimate functions */
 Eigen::Matrix2d estimate_xy_covariance_by_laplace_approximation(
   const Eigen::Matrix<double, 6, 6> & hessian);
-// temporal compatibility until
-//   https://github.com/autowarefoundation/autoware.universe/pull/8124
-// get merged
-Eigen::Matrix2d estimate_xy_covariance_by_Laplace_approximation(
-  const Eigen::Matrix<double, 6, 6> & hessian);
 ResultOfMultiNdtCovarianceEstimation estimate_xy_covariance_by_multi_ndt(
   const NdtResult & ndt_result,
   const std::shared_ptr<
diff --git a/src/estimate_covariance/estimate_covariance.cpp b/src/estimate_covariance/estimate_covariance.cpp
index c49d1c3..120d66f 100644
--- a/src/estimate_covariance/estimate_covariance.cpp
+++ b/src/estimate_covariance/estimate_covariance.cpp
@@ -14,18 +14,6 @@ Eigen::Matrix2d estimate_xy_covariance_by_laplace_approximation(
   return covariance_xy;
 }
 
-// temporal compatibility until
-//   https://github.com/autowarefoundation/autoware.universe/pull/8124
-// get merged
-Eigen::Matrix2d estimate_xy_covariance_by_Laplace_approximation(
-  const Eigen::Matrix<double, 6, 6> & hessian)
-{
-  const Eigen::Matrix2d hessian_xy = hessian.block<2, 2>(0, 0);
-  Eigen::Matrix2d covariance_xy = -hessian_xy.inverse();
-  return covariance_xy;
-}
-
-
 ResultOfMultiNdtCovarianceEstimation estimate_xy_covariance_by_multi_ndt(
   const NdtResult & ndt_result,
   const std::shared_ptr<