Database
[{"ownershipSheetB":{"lrUnitShares":[{"description":"blabla1","lrOwners":[{"lrOwnerId":35780527,"name":"somename1","address":"someadress1","taxNumber":"12345678910"}],"lrUnitShareId":29181970,"subSharesAndEntries":[],"orderNumber":"1"},{"description":"blabla2","lrOwners":[{"lrOwnerId":35780528,"name":"somename2","address":"someadress2","taxNumber":"12345678911"}],"lrUnitShareId":29181971,"subSharesAndEntries":[],"orderNumber":"2"}],"lrEntries":[]}},]
Query
db.collection.find({"ownershipSheetB.lrUnitShares.lrOwners.taxNumber":"12345678910"})