Unfortunately, google...
Unfortunately, google searches for Metropolitan Furniture, I'm sure you know, bring up a kabillion nearly non-navigatable hits. I imagine somebody here at DA can help narrow and refine your search. There are at least a couple mentions in the excellent reference book - titled Sourcebook of Modern Furniture - to a California company that may still be in existence under the Steelcase brand (known as Metro / Metropolitan Furniture Corporation).
Brian Kane (rubber chair, etc) is listed as a designer for the company in the 1980s. Much of their furniture, during this period at least, seems to be designed toward business/large corporation/contract applications.
The rubber chair, as a matter of fact, showed up in mass at a major hospital addition in Lincoln, Nebraska, completed during the 1990s.
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http://metrofurniture.com/about/history.htm
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