Voici ce que j'ai trouvé concernant ces transactions mystérieuses...
Broker Codes: 100 - TSX - TSX Buy-ins (CDS)
In order to support CDS in cases where a seller has failed to deliver a security following a trade, TSX has developed a special "Buy-In" facility to locate alternate sellers capable of immediately delivering the security, therefore enabling CDS to quickly and efficiently clear the failed position.
On a daily basis, CDS provides a list of securities that Participating Organizations have failed to make delivery on.
1:30 PM (1st Cycle) - TSX receives and posts the preliminary Buy-In list. At this point, other Participating Organizations have the opportunity to provide liquidity by submitting Buy-In orders.
2:45 PM (2nd Cycle) - TSX receives and posts the Final Buy-In list. This list identifies the remaining securities that still need to be delivered.
3:00 PM - Cut-off for accepting Buy-In orders
Upon completion of the Buy-In period, TSX allocates fills on an equal by member basis to the sellers and calculates a price. This price is based on the last board lot trade before 3:00 plus a premium.
Buy-In Price = Last Board lot Sale Price + Premium
TSX manually enters these trades that are cleared by CDS on a same-day basis. Between 3:20 and 3:40, TSX Trading Services will provide transaction confirmations. This process efficiently clears failed delivery trades and helps to maintain overall market integrity.