Brothers Patrick, 19, and John Collison, 17, neither of whom have yet completed the Leaving Cert, finalised the sale of their company Auctomatic ! to Canadian firm Live Current Media on Good Friday.
The company, which manages eBay accounts, was founded by the brothers in February last year.
It later merged with the British start-up of cousins Harj and Kul Taggar and then received backing from American investment company Y Combinator, as well as early Google employees Chris Sacca and Paul Buchheit.
Former young scientist of the year, Patrick, who is likely to make a lot more than €1m from the deal, said he is still waiting for the news to sink in.
Speaking from Kerry, where he was mountain climbing, Patrick said there had been strong interest in Auctomatic from well-known Silicon Valley technology companies over the past few months. He said he would travel to Vancouver in May to take up a position as director of engineering at Live Current Media.
Patrick failed in a bid to be permitted to complete the Leaving Cert in one year and instead opted to do his A-Levels, by studying at his home in Limerick and through the Dublin Tutorial Centre.
John, who is in fifth year at Castletroy College, said he is hoping to buy a car with the money he made from the deal.
He intends to finish his studies and work with Live Current Media during the summer.