IP Protection of Kelsall KSS or Cylinder Mold Building Methods

[zstine]

I'm wondering if another designer can prescribe KSS or Cylinder molding without owing royalties to Kelsall (decedents thereof... RIP) or Kurt Hughes? I didn't find anything with a very quick google patent search, but thought I'd ask the experts on here.
Thanks!

 

[Robert Biegler]

I think the period of protection for patents is generally 20 years, but I advise checking. I am pretty sure I read about both KSS and cylinder moulding more than 30 years ago, so they should be out of patent now.

 

[Steve W]

Do you know if patents actually exist? I actually worked on building a KSS hull at a 3 day workshop with Derek. I don't really remember the details of how he determined the dart locations. The workshop was mainly promoting the KSS method but my son and I were mostly there to gain hands on experience with infusion. I do know that KSS has been around at least since the late 1990s as I bought a video from Derek about 98.