On the ASX, the code "S3 XT" indicates that the trade was...

On the ASX, the code "S3 XT" indicates that the trade was executed through a crossing mechanism, where the buyer and seller's orders were matched directly without going through the open market. In essence, "S3 XT" means that a large block of shares was traded directly between a buyer and a seller without going through the usual auction process on the ASX. This is often done for larger trades to avoid disrupting the market or to obtain a better price.

If we see more of these it "might" even have some implications of a possible looming T/O bid. Just another bit of info people might want to factor into their trading analysis BUT never forget, do your own research.