In Latvian and Estonian existential clauses, the subject’s case form alternates between nominative vs. genitive (in Latvian) and nominative vs. partitive (in Estonian). This article is a study of the case-alternation systems of existential clauses and related clause types, locative and possessive clauses in these languages. It includes a corpusbased analysis of Latvian existential clauses that is being compared with Estonian corpus-based findings on similar clause types in Estonian. *** "Subjekti käändevaheldus läti ja eesti keele eksistentsiaallausetes" Nii eesti kui ka läti keeles esineb subjekti käändevaheldust. Läti keeles saab subjekt olla lisaks nominatiivile ka genitiivis, eesti keeles lisaks nominatiivile ka partitiivis. Artikl...