Since the early 1990s until 2007, Melchers was a major sponsor of the Dutch Bridge Federation (NBB). In 2008 Melchers started his own professional bridge team. He "provided major funding for the 2011 world bridge championship held in the Netherlands" (in Veldhoven, hosted by NBB).
His daughter, Claudia, was the victim of a kidnapping in September 2005. She was released after two days of confinement.
On the Forbes 2016 list of the world's billionaires, he was ranked #722 with a net worth of US$2.4 billion.