What sectors will see the greatest net exposure change due to the 42 additions and 56 deletions in the MSCI ACWI Index?

Answer

The press release you quoted tells us only the headline numbers for the August 2025 MSCI ACWI Index review:

It does not disclose the sector classification of those 42 additions or the 56 deletions. Because net‑exposure changes are calculated by comparing the sector weightings of the securities that are coming in versus those that are going out, the specific sectors that will experience the largest net‑exposure shift cannot be identified from the information that was provided.

Why the sector impact can’t be determined from the release

1. No sector breakdown – The announcement lists the total number of additions and deletions, but it does not break them down by GICS sector (e.g., Technology, Financials, Health Care, etc.).
   
2. No market‑cap weighting details – Even if we knew the sectors, the net‑exposure effect also depends on the market‑capitalisation of each security. A small‑cap addition in a given sector may have a negligible impact, while a large‑cap deletion could move the sector weight dramatically.
   
3. Only a few “largest” additions are named – The three biggest additions to the MSCI World Index (Rocket Lab Corp, SoFi Technologies, and Affirm) give us a hint about the types of companies that are entering the broader MSCI family, but they are not part of the ACWI Index list and they do not represent the full set of 42 additions. Moreover, the press release does not say whether any of those three are also being added to the ACWI Index.

What we can infer (with strong caveats)

While we cannot pinpoint the exact sector with the greatest net‑exposure change, we can make a few educated guesses based on the limited company information that is mentioned:

If any of these three firms are also part of the ACWI additions, the Financials and Industrials sectors would be among those most likely to feel a net‑exposure shift. However, without confirmation that they are part of the ACWI changes, this remains speculative.

What would be needed for a definitive answer

To identify the sector(s) with the greatest net‑exposure change, MSCI would have to publish—or we would need to obtain—the following data:

With those pieces of information, the calculation would be:

[
\text{Net sector exposure change} = \sum{\text{added securities in sector}} \text{weight} \; - \; \sum{\text{deleted securities in sector}} \text{weight}
]

The sector with the largest absolute value of this result would be the one experiencing the greatest net exposure change.

Bottom line

Based solely on the news excerpt you provided, we cannot determine which sectors will see the greatest net exposure change in the MSCI ACWI Index. The announcement does not include sector‑level details, and the few companies named are not confirmed as part of the ACWI changes. A precise answer would require the sector breakdown and weightings of the 42 added and 56 deleted securities. If you can obtain that supplemental data (e.g., from MSCI’s full index‑review documentation or a detailed spreadsheet of the changes), we would be able to compute the net‑exposure impact for each sector and identify the one with the largest shift.