Pieper returned to the Netherlands in 1998. For one year he was board member of the Dutch electronics giant Philips by invitation of Cor Boonstra, then Philips' president. This involvement ended abruptly in May 1999 when Pieper got involved in the claimed coding technology of Jan Sloot, a connection Pieper made on behalf of Philips. Philips officially decided not to use the technology. Pieper then decided to support the invention as a private investor and later also as board member, though Sloot's claimed huge compression is mathematically impossible. The inventor died of a heart attack shortly after he demonstrated his technology to a group of 20 investors and technology companies in the summer of 1999. After one year, Pieper ended his employment at Philips with a severance package of undisclosed value.