I have done some minimal searching for such a directory, and found that ARTnews has published an International Directory of Corporate Art Collections.  I called the phone number associated with this directory located in Largo, FL, but had no luck in reaching anyone to obtain this
publication.  The website where I found this information is:
http://www.cftech.com/BrainBank/CORPORATEADMINISTRATION/CorpArt.html

At the JCPenney Company, Inc. headquarters in Plano, Texas (just north of Dallas), we maintain a company archives, a small historical museum, and corporate art collection.  I would be happy to answer any questions you have regarding corporate collections.

--
Jeff Pirtle
Museum / Archives Project Manager
JCPenney Company, Inc.
P.O. Box 10001
Dallas, Texas 75301- 4118
(972) 431-7926
http://www.jcpenneyinc.com/archive/archive.htm

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