When you register with Shutterstock you are asked for two names: Full Name and Display Name.
Your Full Name must be your legal name as it appears on your identification documents. This name will not be displayed publicly on our website and is the name to which royalty payments will be made, also known as "Make payments to" name, so you may not use a nickname. Payments and registration can also be made to a business name. Learn more about registering as a business here: Can I register for a contributor account as a business?
Your Display Name will be displayed publicly next to your content on www.shutterstock.com and will be used as your Copyright Name by subscribers when giving photo credit. You may use an artist name, nickname, or pseudonym as your display name and it can be changed in the Public Information section after your account has been approved.