When creating an Apple Developer Account, if you choose the Entity type Company / Organization, you will be asked for a DUNS number in the next step.
What is D-U-N-S number?
"D‑U‑N‑S" (which stands for Data Universal Numbering System), is a system used to maintain up-to-date and timely information on more than 280 million global businesses. It is a proprietary system developed and regulated by Dun & Bradstreet (D&B). It assigns a unique numeric identifier - referred to as a DUNS number - to a single business entity.
Why do I need a DUNS number?
Apple has a policy where they verify every single company before letting them create a developer account. To make the verification easier and faster, Apple requests all businesses to enter their DUNS number.
Note: Currently, this method of obtaining a DUNS number is absolutely free.
If you don't have a DUNS number, or if you're not sure whether you have one or not, or if you have one and have forgotten your DUNS number, you can follow these steps to acquire your DUNS number.
Step 1: Go to https://developer.apple.com/enroll/duns-lookup/#/search and login with your Apple ID
Step 2: Enter all the details requested of you and press continue
Step 3: Verify if all the details are correct, click on agree to Terms & Conditions, and then click the Submit button
Step 5: Your information will be processed and you'll receive a confirmation email regarding the same. You will receive your DUNS number 2-3 business days once the information is processed.
The process may get delayed by a few days if the D&B team requires additional information from you to verify your registered business. Sometimes this depends on the country of your business.
Once you receive your DUNS number from D&B, you can proceed with creating your developer account by following this link: https://developer.apple.com/enroll/.
With your DUNS number, you can now create your Apple Developer account to proceed with launching your app!