Buying medical marijuana in Massachusetts got a little less anonymous Thursday morning, when the state’s lone pot dispensary accidentally shared some of its patients’ email addresses with other patients.

Salem’s Alternative Therapies Group sent an email addressed “Dear Patient,” to 157 email addresses. A copy of the email obtained by Boston.com listed the addresses in the CC line, meaning the recipients could see each other’s addresses. The dispensary had meant to send the email as a blind CC, or BCC, which would have kept the email addresses from being seen by all.

The breach of patient confidentiality came just as medical marijuana begins to take hold in Massachusetts. Alternative Therapies Group opened in late June, and others have obtained licenses to sell marijuana legally. [Read more at the Boston Globe]