What are the acceptable forms of proof of chamber membership?

The following are acceptable forms of proof of chamber membership:

• A letter from the Chamber of Commerce stating the employer is a member in good standing.
• An email from the employer’s declared Chamber of Commerce stating the employer is a member in good standing. The email must specify the sender’s name and title, and must show the senders’ email address, date, and timestamp.
• A copy of a cancelled check or credit card receipt that indicates payment of membership dues including the name of the employer’s declared chamber of commerce.