Who allowed the creation of super PAC's?

Super PACs were allowed to be created following the 2010 Supreme Court decision in the case of Citizens United v. Federal Election Commission. The Court ruled that restrictions on independent political expenditures by corporations and unions violated the First Amendment's free speech protections. This decision effectively enabled the formation of Super PACs, which can raise and spend unlimited amounts of money to advocate for or against political candidates, as long as they do not coordinate directly with the candidates' campaigns.