A wholesale trading facility that allows traders to buy or sell large numbers of securities bilaterally outside of the public market. Because trades conducted in a block trading facility are typically between two parties, prices are set with certainty and execution is done without delay. Institutional investors use block trading facilities for transactions involving large numbers of shares.




Taobiz explains Block Trading Facility - BTF
When shares are traded in a block trading facility they are transacted in large lots. The size of the lots can vary, but traders are generally not permitted to aggregate multiple, separate orders in an effort to meet minimum volume requirements. Securities traded though a block trading facility are not subject to market fluctuations because they are not publicly visible, making this sort of trade more like a private contract between two parties.