Deubiquitinating enzyme that removes conjugated ubiquitin from specific proteins to regulate different cellular processes. Regulates cell proliferation by deubiquitinating and inhibiting RCE1 thereby controlling the small GTPases NRAS and HRAS localization and activation. In parallel, mediates deubiquitination of CDC25A, preventing CDC25A degradation by the proteasome during the G1/S and G2/M phases promoting cell-cycle progression. Also regulates cell proliferation and apoptosis through deubiquitination of SUDS3 a regulator of histone deacetylation. Through activation of the Rho family GTPases RAC1A, CDC42 and RHOA, regulates cell migration. Through the cleavage of 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains of the cytoplasmic innate immune receptors RIGI and IFIH1 stimulates the cellular response to viral infection. {ECO:0000269|PubMed:14699124, ECO:0000269|PubMed:17109758, ECO:0000269|PubMed:19188362, ECO:0000269|PubMed:20147298, ECO:0000269|PubMed:20228808, ECO:0000269|PubMed:20368735, ECO:0000269|PubMed:20388806, ECO:0000269|PubMed:21239494, ECO:0000269|PubMed:21448158}. This is the function of Ensembl gene identifier ENSG00000223443 (USP17L2, ubiquitin specific peptidase 17 like family member 2).