Do I need to enter a credit card number to use DO Patent? Merrill Cook August 27, 2025 14:01 No, a credit card is not necessary. The first 50 pages are FREE every month. Related to Billing DO Patent Related articles For DO Patent, what does “Available Credit” mean in the Billing tab? How do I know how many pages were analyzed as paid actions by DO Patent? How do I start using DO Patent?