HONA
Honeywell Aerospace Inc. Common Stock
stock NASDAQ

Why not HWM over HONA?

This is very helpful, especially the distinction between the quarterly rebalances and the corporate-action cases.
I think we may be running into exactly the distinction you’re describing. For the March–September 2026 window I’m reconstructing, the scheduled S&P 500 rebalances are indeed March 23, June 22 and September 21, but there are also several intra-quarter constituent changes associated with spin-offs, acquisitions, mergers, etc.
For example, I’m seeing cases such as FDXF/EPAM and HONA/CAG where the security-level event dates don't line up with a quarterly rebalance.
A few things I’d love to clarify if you know them:
1. When you say an equity “stays until it is replaced, merged, or delisted,” do you mean that as a practical reconstruction rule, or do you have a specific S&P source for that rule?
2. For an acquisition for cash, do you know what source you would use to determine the exact S&P deletion date — the S&P announcement, expected delisting date, exchange notice, SEC filing, or something else?
3. Do you know whether S&P publishes a historical list of these intra-quarter corporate-action deletions, separate from the quarterly rebalance announcements?
4. For a merger where the surviving company is already an S&P 500 constituent, do you know how the historical constituent/security record is represented? Is the acquired security simply terminated and the surviving constituent's float/share count updated?
5. For a spin-off where the parent remains in the S&P 500 and the new spin-off becomes a constituent, do you know whether S&P treats the new security as a new constituent/security identity or as some form of continuation?
6. Do you know whether S&P's historical constituent data includes identifiers such as CUSIP/FIGI, or whether the public announcements are essentially the only way to reconstruct those mappings?
7. One thing I’m particularly curious about: if you had to reconstruct the drop-outs for a short historical window like March–September 2026 without access to a commercial historical constituent database, what would your source hierarchy be?
Would it be something like:
S&P announcements → SEC/exchange corporate-action records → ETF holdings as cross-check
or is there another source you would put between those layers?
The IVV monthly limitation makes sense to me. I’m mainly trying to avoid using it to resolve a genuine security-identity/effective-date ambiguity.