I've come across several examples of these tables for sale lately and they bare a striking resemblance to Kagan's biomorphic 412 table.
Where they produced during the same period?
Apparently Pearsall's Jack's table was produced by Craft & Associates but I have not been able to obtain any additional information on the table.
How does one determine authenticity? Are there markings on the table base?
This might help a little--
http://vladimirkagan.typepad.com/vladimir-kagans-blog/2015/09/vintage-vs...
Why are you asking the same question twice?
http://www.designaddict.com/forum/Identification/Vladamir-Kagan-Model-412
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