Do you mean Steemit.com? The blogging website that uses the blockchain called Steem? Steemit Inc is a company registered in the USA that owns Steemit.com. The blockchain is public and not owned by anyone in a legal sense. The blockchain is a collaborative effort by people called witnesses who run the blockchain software on their own computers called Steem witness nodes. They get paid in STEEM (the cryptocurrency) by the blockchain. The people who get to be witnesses are elected in an ongoing vote by all owners of Steem Power whose votes have weight in proportion to the Steem Power on their account.