It was speculated Soborg pipes were made by Søren Refbjerg Rasmussen. Now it seems to be certain that these have at least been produced in his wokshop in Søborg, Denmark, although not necessarily by Rasmussen himself but probably by his employees.
Bob Taylor reported a brief correspondence with Rasmussen regarding a Soborg pipe Taylor purchased in April of 2007. Rasmussen indicated Soborg pipes were made about 30 years ago, and were not made by him personally but presumably by others working for him. It's a bit hard to decipher, but it appears pipes with a short shank were saved, and then finished up every 6 months and sold as Soborgs. They were mostly sold to England, and the U.S. markets. Most of them had a rough (Plateaux) top. The example Taylor purchased has the short shank, but with a smooth top.
After Rasmussen's retirement the content of his workshop was purchased by Poul Rasmussen (another one) including equipment, pipes and paperwork. These files revealed again that the Soborg pipes did come from Søren Rasmussen.