Ann: 2024 Half Year Results - Investor Presentation, page-59

Yeah, sort of, don't forget that the index volume was known in advance - so there would be funds that bought shares some time ago specifically to sell into the volume on Friday.

DRO is quite small on the big scale of things, so if a fund systematically buys all the index shares as soon as the changes are announced, they can likely make a profit on average across all of them. They can easily hedge out the market beta also, so it's just a trade on whether the shares going into an index outperform the market.

I did a bit of that sort of trading for a big firm many years ago. Sounds fun... but you're trading so many different shares in a day you don't even know anything about the company other than what the ticker-code is and how many you need to buy. Nowadays they'd automate a lot of that.