If companies do not have to get certified, then any Tom, Dick, or Baltia could operate an Airline.
Baltia tried to get their Air carrier certification using a 39 year old 747 and failed miserably.
Then they tried to buy SongBird Airways certificate and failed because they could not get the money to close the deal.
During Baltia's failed attempt to acquire SongBird, the DOT issued the following:
We revoke the certificate of public convenience and necessity issued to Baltia Air Lines, Inc., by Order 2009-3-7 authorizing it to engage in scheduled foreign air transportation of persons, property, and mail.
The DOT also ratted Baltia out: "In addition, the Federal Aviation Administration informed us that Baltia withdrew its application for air carrier certification."