The Burma-Vita Company was sold to Philip Morris, Inc. in 1963. Shorty thereafter, the executives decided to reduce the number of signs in favor of spending on other advertising media. They decided to take down all signs as soon as possible, and crews were dispatched to travel the country to remove all signs. It is possible a few evaded removal, because completeness of company records was not a major concern. The standard was six signs in all, with BURMA-SHAVE usually, but not always, on the last sign.
One last one:
IF YOU
DON'T KNOW
WHOSE SIGNS
THESE ARE
YOU CAN'T HAVE
DRIVEN VERY FAR.
Thanks for the explanation. I imagine a lot of them were stolen, especially when people discovered they were all going to be removed!