At a glance, the response would be designed by Arne Hovmand Olsen. However, there are some very similar designs in the UK, which were made by Meredew. I'm a bit rusty on the details of each, but I think yours are Meredew.
Googling and finding a marked set that matches yours would confirm.
It is possible that Hovmand Olsen himself designed the chairs for Meredew, similar to how Ib Kofod Larsen designed a line for G-Plan; but I have not seen any evidence that was the case.
@lexi, thank you so much for sharing your knowledge! Can I ask how do you know so much about MCM furniture? Is it your passion or work/ business?
I also have a lounge chair that came from the same house as EON chairs, but it does not seem to be made by Elliotts of Newbury, UK...Any chance you can recognize it as well?
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