diff --git a/ProcessLib/RichardsMechanics/ComputeMicroPorosity.h b/ProcessLib/RichardsMechanics/ComputeMicroPorosity.h
index a6429aaf844b42d0cfbaf9802d41fc6aa1b08d7b..79ecf3d9c3200a946659f83f34ce8ef43805967c 100644
--- a/ProcessLib/RichardsMechanics/ComputeMicroPorosity.h
+++ b/ProcessLib/RichardsMechanics/ComputeMicroPorosity.h
@@ -187,7 +187,7 @@ MicroPorosityStateSpace<DisplacementDim> computeMicroPorosity(
             i_sigma_sw, i_p_L_m) = -dsigma_sw_dS_L_m * dS_L_m_dp_cap_m;
 
         jacobian(i_p_L_m, i_phi_m) =
-            rho_LR_m * (delta_S_L_m + phi_m * delta_e_sw);
+            rho_LR_m * (delta_S_L_m + S_L_m * delta_e_sw);
 
         jacobian(i_p_L_m, i_e_sw) = -rho_LR_m * S_L_m * (alpha_B - phi_M - phi_m);