The option to buy or sell insurance, etc., on the open market; (British) the option of selling a personal pension fund to another pension provider on retirement, so as to obtain a larger annuity.
Origin
1970s; earliest use found in The Times.
Definition of open market option in US English:
open market option
noun
The option to buy or sell insurance, etc., on the open market; (British) the option of selling a personal pension fund to another pension provider on retirement, so as to obtain a larger annuity.