Blockstream is a company developing blockchain technologies that employs some of the Bitcoin Core developers and the main developer of the Lightning Network for

Blockstream is a company developing blockchain technologies that employs some of the Bitcoin Core developers and the main developer of the Lightning Network for off-chain transaction channels. (Bitcoin Core is the software usually used to run full Bitcoin nodes; it's basically Satoshi's original client, renamed to clarify that users don't have to choose it as their wallet back when running a full node started to become user-unfriendly.) It's become associated with a conspiracy theory that claims the entire Bitcoin Core development community, including the developers not employed by them, is plotting with the banking industry to sabotage on-chain Bitcoin in order to force everyone to use banks to transfer Bitcoins, basically.