Going from the liner notes on various commercial issues plus online stuff, I've arrived at this 
list. Comments most welcome and appreciated.

1. Bell Labs/Stokowski - 1932

2. EMI/Blumlein - 1934

3. Bert Whyte/Magnecorder -- 1952

4. Emory Cook -- 1952

5. RCA -- 1954 (earliest experimental recordings no longer exist, first commercial stereo recordings 
made in 1954)

6. Decca -- 1954

7. Teldec -- 1954

8. Mercury -- 1955 (experiments started as early as 1952 but no tapes exist pre-1955)

9. what about Livingston with the hotel polka bands, was that 1954 or even 1953?

10. what about Sound In The Round, 1955?

Thanks again for comments/clarifications/facts.

-- Tom Fine