Sharing Amazon Prime just got more difficult

It’s no secret people share Amazon Prime accounts. As CNNMoney put it, “at $99 per year, Amazon Prime was a great deal. Sharing it between five people was even better.”

But Amazon Inc. (Nasdaq: AMZN) is putting measures in place to stop it.

Previously, members could add up to four people to their Prime account by entering their names, relationships, birthdays and email addresses. Invitees would need to know the member's month and day of birth to accept the invitation, according to CNNMoney.

Now, “Amazon Household” only allows sharing with one other adult and you have to share more than just your birthday – you have to share financial information.

According to CNNMoney, both adult account holders need to authorize each other to use credit and debit cards associated with their Amazon accounts for purchases. While both accounts can maintain their payment methods, you can see and use each others' cards, which may be awkward if sharing with, say, a co-worker.

The new feature took effect July 31.

Read more from CNNMoney.