Involved in the inactivation of MAP kinases. Dephosphorylates ERK, JNK and p38 MAP-kinases. Plays a negative role in TCR signaling by dephosphorylating MAP3K7 adapter TAB1 leading to its inactivation (PubMed:24403530). . This is the function of DUSP14 (dual specificity phosphatase 14, Ensembl gene identifier ENSG00000276023).