Also Ethereum switched to proof of stake. Which means that the "stakeholders" (shareholders) are voting what transactions go into the ledger. Bitcoin is proof of work still.
With proof of stake, a staker eventually gets an opportunity to follow the validation rules and put some transactions in a block. If they don't properly follow the rules, they will get slashed. If they don't submit a block when it is their turn, they will get gently slashed.
In proof of work it is a free-for-all with whoever has the most hashing power winning block submission more frequently. If they submit a block that doesn't follow the validation rules they keep all of their (physical silicon) hashing power and the block is ignored.