If you buy DWDP, you will get 1 share of new DOW for every 3 shares of DWDP you own when DOW is spun off on 4/1/19. (The new DOW starts trading on 4/2/19.)
On the other hand, if you buy DWDP-WI (“when issued”), you will not receive shares of DOW in the spin-off.
Currently, DWDP is trading at about $52, while DWDP-WI is trading at about $36. The difference between these two prices is how much value investors are ascribing to the DOW spin-off.
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