  This paper presents a corrigendum to Theorems 2 and 3 in Siddiqui S, Gabriel
S (2013), An SOS1-Based Approach for Solving MPECs with a Natural Gas Market
Application, Networks and Spatial Economics 13(2):205--227. In brief, we revise
the claim that their L-penalty approach yields a solution satisfying
complementarity for any positive value of L, in general. This becomes evident
when interpreting the L-penalty method as a weighted-sum scalarization of a
bicriteria optimization problem. We also elaborate further assumptions under
which the L-penalty approach yields a solution satisfying complementarity.
