The act uses defines the word "initiate" and the SMTP only allows "asking if an address exists" via initiating a send (and then dropping the connection before a message is sent).
> The term "initiate", when used with respect to a commercial electronic mail message, means to originate or transmit such message or to procure the origination or transmission of such message, but shall not include actionsthat constitute routine conveyance of such message.
I also don't think (but with less certainty) that what isn't fully sent counts as a message, as the primary purpose is verifying if the address exists. Message is defined as
> any electronic mail message the primary purpose of which is the commercial advertisement or pro-motion of a commercial product or service