there are various investment institutions, such as...

there are various investment institutions, such as superannuation funds, mutual funds, pension funds and private funds, that track the performance of the ASX100/200, which are the top 100/200 listed companies on the Australian Securities Exchange. These funds have billions, if not millions, of dollars to invest.

For instance, if you have an Australian Super Direct Invest account, you can only invest in shares that are part of the ASX 200. Therefore, there is money sitting around that these funds cannot invest in good companies like NEU, until it gets included in the ASX100/200.

Once a company is included, the fund managers get the green light to invest.Often, if these funds follow the ASX100/200 index, they must purchase the included stocks, depending on the fund's investment philosophy.

Being included in the index is a significant advantage for both the shareholders and the company because it is open to more investors with a lot of money.Note that this does not mean that large funds cannot invest in NEU today, but rather specific fund products that are restricted to only buying ASX100/200 or can only buy a certain percentage of stocks that are not part of the index.

Therefore, more money can flow into NEU after it is included in the index.However, it's important to take everything with a grain of salt because some prop trading firms may try to front-run this and move the market higher before the stock gets included and get out on the day of the rebalance, which can be very tricky.This is just my opinion.

+ what @Vapor said here