Negative options plans are widely used by book clubs, record clubs and other mail order merchandisers.Under a negative option plan, your failure to say “no” means in effect you have said “yes”. 

A negative option plan is a contractual agreement whereby the seller periodically sends to its subscribers an announcement that identifies books, records, or other merchandise he proposes to send the consumer.Unless the subscriber instructs the seller not to send the merchandise by a certain date or within a certain time period, the merchandise will be sent and the subscriber is billed. 

There is nothing illegal about negative option plans. However, refer to CGS Title 42 Chapter 126b