Deubiquitinase, which cleaves 'Lys-11'-linked polyubiquitin chains. Might be required for PA28-20S proteasome assembly (Probable). {ECO:0000269|PubMed:20622874, ECO:0000269|PubMed:23827681, ECO:0000305|PubMed:31997314}. This is the function of Ensembl gene identifier ENSG00000169918 (OTUD7A, OTU deubiquitinase 7A).