Disclosed herein is a transmission apparatus for transmitting AV (Audio/Video) content, including: an acquirer configured to acquire an estimated number of audience terminals indicative of an estimated number of reception apparatuses receiving the AV content; a computer configured, in conjugation with the AV content, to compute, on the basis of the estimated number of audience terminals, a validity probability of trigger information associated with control of an application program to be executed in the reception apparatus; a generator configured to generate the trigger signal including the computed validity probability; and a transmitter configured to transmit the generated trigger information with the AV content.