Sarbanes-Oxley made it much more complicated to sell to public investors than to private ones. You pretty much have to hire staff whose only job is to ensure being compliant.
Public companies always had pretty strict reporting requirements leading to substantial overhead. If you take the public's money they have a right to be informed and to a minimum standard of corporate structure and governance.
Sarbanes-Oxley was instituted in the wake of the Enron and Worldcom (and others beside) scandals (which led to the demise of accounting giant Arthur-Andersen, which - surprisingly - survived in some form because the verdict against them from the Enron debacle was eventually overturned by the supreme court) which severely undermined the public confidence in Wall Street.
As a result the already substantial reporting requirements for public companies were ratcheted up several notches further increasing the overhead. So yes, Sarbanes-Oxley made it more expensive to be listed on the stock market and therefore to be trade publicly but the difference was always there, also before SOX.
Sarbanes-Oxley was instituted in the wake of the Enron and Worldcom (and others beside) scandals (which led to the demise of accounting giant Arthur-Andersen, which - surprisingly - survived in some form because the verdict against them from the Enron debacle was eventually overturned by the supreme court) which severely undermined the public confidence in Wall Street.
As a result the already substantial reporting requirements for public companies were ratcheted up several notches further increasing the overhead. So yes, Sarbanes-Oxley made it more expensive to be listed on the stock market and therefore to be trade publicly but the difference was always there, also before SOX.