What are the applications of Quadrupole Neodymium magnets?

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Quadrupole Neodymium magnets are subject to numerous patents, particularly those held by GE and Sumitomo, which restrict the use of cobalt-containing magnets and those with a tetragonal crystalline structure. Cobalt doping in the iron site may enhance properties like critical temperature and uniaxial anisotropy, but specific patent information on this topic is scarce. High-energy and high-temperature magnets often utilize these advanced technologies, raising questions about their licensing requirements. Quadrupole magnets, characterized by their four poles, are commonly found in particle accelerators and can resemble ordinary bar magnets in appearance. Understanding the patent landscape is crucial for applications involving these specialized magnets.
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There are lots of patents on Neo magnets and they are difficult to sort out. Some of the patents restrict the use of the magnets that contain cobalt and/or have a tetragonal crystalline structure.
Does someone know:

What types of magnets contain cobalt?
What types of magnets have a tetragonal structure?
 
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Most NdFeB magnet patents are held by GE and/or Sumitomo. You should check with them.

I expect there's a lot of literature on Co doping in the Fe site (I think it increases Tc and uniaxial anisotropy, up to some optimal doping), but know absolutely nothing about patents here.
 
The Neomax (Sumitomo) and Magnequench (GM) patents do require licences for Neo magnets that contain cobalt and have tetragonal structures. I am curious if all high energy (>30MOe) and high temperature (>110C) magnets use this type of technology.
 
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Does anyone know who has the patents on Quadrupole Neodymium. I found a video of one on YouTube:

You can find these magnets in particle accelerators, and they have 4 poles (Quadrupole). This one is a permanent magnet, and without the video I couldn't tell the difference between it and an ordinary bar magnet.
 
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