Hydrolyzes bioactive fatty-acid esters of hydroxy-fatty acids (FAHFAs), but not other major classes of lipids (PubMed:27018888). Show a preference for FAHFAs with branching distal from the carboxylate head group of the lipids (PubMed:27018888). . This is the function of AIG1 (androgen induced 1, Ensembl gene identifier ENSG00000146416).