WhatsApp gives OBA status to only highly reputed businesses. With the OBA status:
The name of the business will come rather than the number irrespective whether the user has saved the contact or not
There will be a green tick in front of the business name
The green badge next to the contact's name confirms that this is an authentic and notable business account giving it higher credibility and less chances of people considering it as a SPAM
You'll need to contact TARS CSM in case you want to submit the OBA application.
Note: Once an OBA application is rejected, the business can submit another OBA request only after 2 months