Several developers, miners, and researchers reported that Bitcoin mining developer name Marathon Digital mined an invalid block 809478.
means the marathon digital got 6.25BTC for mining an invalid block?
do the invalid block which got mined is placed in a real bitcoin blockchain or any other blockchain? or not added to any blockchain?
and if the invalid block was mined, so of course there were wrong transaction(or transaction from 0 balance wallet) or double spending was happened?