A share buyback announcement only indicates the purchase capacity, while the actual execution takes place over several months. This article explains the difference between authorization and execution, the constraints involved, and how to interpret supply and demand.
A share buyback announcement only sets the acquisition capacity, consisting of the maximum number of shares, maximum amount and acquisition period, while the actual purchases are carried out separately. Rather than judging the progress of the authorization solely from the surface of the news, investors should track actual purchases through the monthly Reports on the Status of Acquisition of Treasury Shares, which show how much of the authorization has been used.
The monthly reports record how many shares were bought, at what price and when, leaving a trail of the purchases. It is said that the actual supply-and-demand picture can be understood by examining the pace at which the authorization is being used. The buyback capacity for fiscal 2025 is ¥22.325 trillion, up 18% from the previous fiscal year, while purchases from January to May reached ¥16.2 trillion, a record high; the number of programs is reportedly trending downward.
Share buyback execution is subject to constraints on volume, timing, price and the use of a single broker, and blackout periods also apply before earnings announcements. Larger authorizations take longer to use, and supply-and-demand dynamics that span an earnings announcement are said to differ from one stock to another.
In practice, execution is algorithmic, with rules said to include following VWAP, avoiding chasing the order book and placing limit orders at or below the most recent price. ToSTNeT-3, an off-auction trading system, can be used to purchase a large number of shares at once, although such transactions are often carried out during the morning session.