IMUGENE CHART. TA only, page-9073

After ASX200 inclusion, I see the following needing/wanting to hold sizeable amounts of shares.

1. Passive (Index) EFT funds
2. Active fund managers who benchmark against the ASX200 performance and will usually hold a proportion but not necessarily in exact percentage of the index.
3. Other fund managers, who have a flexibility whether to hold or not.
4. Super funds, some/most of which have choice options for their members, similar to the three above, namely Indexed, Active or a bucket which comes under various names such as 'Balanced' or 'Growth' and includes proportions of shares, real estate, infrastructure, bonds etc. or 'Australian Shares' which is close to 100% share holding, plus a bit of cash.
5. Other institutional Investors

My understanding is that the two weeks notice gives funds time accumulate the shares that they need, or to sell shares that have been removed from the index.

Funds do not wait until the 20th to start accumulating.

Most funds would already be accumulating, or will be accumulating in the next two weeks. Others (which have discretion) may wait until days or weeks after the 20th.

My observation (in normal general market conditions) is that share prices rise on the first trading day after inclusion announcement and continue to rise up to and after the effective date.

Sometimes the price does fall due to changed specific market conditions or company news.

On Monday, @davybabyk noted that all shares that were included in the ASX200, fell in price.

https://hotcopper.com.au/posts/58105641/single

From the following chart it can still be seen that there have not been the increases that usually start to occur, although XJO has risen slightly.

It is surprising that the shares that have been removed have held up quite well - 'It must be different this time' Why???