what is to be announced tba 
to be announced or tba in bond trading is a term that describes forward settling of mortgage backed securities mbs trades pass through securities issued by freddie mac fannie mae and ginnie mae trade in the tba market and the term tba is derived from the fact that the actual mortgage backed security that will be delivered to fulfill a tba trade is not designated at the time the trade is made these securities are announced 48 hours prior to the established trade settlement date 1tba may also be used to denote a pending corporate announcement or other pieces of information that is yet to be determined tbd understanding tbaa tba serves as a contract to purchase or sell an mbs on a specific date but it does not include information regarding the pool number number of pools or the exact amount that will be included in the transaction an mbs is a bond that is secured or backed by mortgage loans loans with similar traits are grouped together to form a pool and that pool is subsequently sold to stand as collateral for the associated mbs 1interest and principal payments are issued to investors at a rate based on the principal and interest payments made by the borrowers of the associated mortgages investors receive interest payments on a monthly basis instead of semiannually the settlement procedures of mbs tba trades are established by the securities industry and financial markets association 2this is because the tba market assumes mbs pools to be relatively interchangeable the tba process increases the overall liquidity of the mbs market by taking thousands of different mbss with different characteristics and trading them through a handful of contracts the buyers and sellers of tba trades agree on these parameters issuer maturity coupon price par amount and settlement date 3each type of agency pass through security is given a trade settlement date for each month trade counterparties are required to exchange pool information by 3 p m est 48 hours prior to the established settlement date trades are allocated in 1 million lots 45the tba market is the second most traded secondary market after the u s treasury market 4