In my country, the communist party (very watered down version of communism but still) is behind/aligned with most unions and they defend that companies should either be owned by the employees (co-ops) or employees should have a stake and saying on companies governance.
We have another left-wing party that even defends that failing companies should be returned to the employees, with government backed funding (loaned) if necessary to recapitalize the business and relaunch the company under employee governance.