Kepler-40 was first observed by the Kepler spacecraft, a NASA satellite that searches for planets in transit (crossing in front of and dimming) their host stars, from May 13, 2009, to June 15, 2009 in its first days of operation.
The discovery of Kepler-40b demonstrated that smaller telescopes, such as SOPHIE, are effective when used as follow-ups to space missions like Kepler.