3/16/2026 at 2:10:19 AM
To explain the mechanism simply.Suppose you had a index of 100 companys each with a market cap of 1 G$ for a total of 100 G$. You have passive investors owning 20 G$ of that index, amounting to 20% of the total, 20% of each company, and 200 M$ per company.
You then rotate out a company for a new one also worth 1 G$. The index is still 100 G$, but to match the index you are contractually required to sell your 20% ownership of the old company and are contractually required to buy 20% ownership of the new company.
However, the newly added company only released 5% of its shares to the public and the founder kept hold of the remaining 95%. Those fund managers are contractually obligated to buy 20% of the newly added company, but only 5% is available. Like a short squeeze, where the squeezer buys and holds supply so there are not enough purchasable shares to cover the shorts (obligated ownership), this is a financial divide by zero.
To get the remaining 15%, which they are contractually obligated to acquire, they must purchase from the founder. As they are in violation of their contract if they fail to acquire the remaining 15%, the founder now has complete control to dictate any price they want.
That is the scheme described: how to short squeeze retirement funds who do not even have shorts for fun and profit.
Note that this is a minor variation on my post on the same underlying topic here: https://news.ycombinator.com/item?id=47392325
by Veserv
3/16/2026 at 9:40:56 AM
This is wrong in multiple ways.First: 5x5 is 25, not 20. So it's 25% rather than 20%
Second: they only have to buy the 25% of the listed shares.
To take your 1 Trillion example: if SpaceX has a total market cap of 1T, but only 500b get listed on NASDAQ, and the free float is 5%, the index will weigh SpaceX at 25% of the listed shares, which means it will be weighted at 500 * 0.25 = 125b.
And also note that index ETFs have tracking errors all the time (that's why arbitrage traders still have business!), and the ETFs themselves could also track the performance of SpaceX via derivatives instead of buying the stock. And I think, there are many investors of SpaceX who would like to sell some shares. Fund managers won't have an issue finding their phone numbers.
by super256
3/16/2026 at 6:26:01 PM
It is amazing that you can complain about a simplified example and then both misunderstand it and get literally every single one of your "corrections" wrong.1. As I made abundantly clear, 20% is the passive ownership of the index. It has no relation to the index weighting which you are mentioning.
2. They have to buy 20% of the weighted value. The actual weight is 5x the float. I chose to use a weight of 100% instead of a multiple of the float as a simplification since any weighting greater than the float could result in a squeeze given a large enough passive/obligated ownership pool. However, since I was expecting this sort of "correction", I chose 20% passive ownership of the index (i.e. 1/5) so that they would have to buy 20% of the 25% which is 5%, the same amount as the 5% float. This would result in the passive investors having to purchase all of publicly traded stock which is the divide by zero point that spikes the stock. So, even if your correction was not wrong, I also already countered it.
3. Tracking errors are distinct from intentionally not tracking the index you are contractually obligated to match. You are insinuating that the target of these financial manipulations will defend their clients by ignoring their legal obligations and blaming it on "tracking error". While that is possible, I see no reason to assume that will be the case upfront or to do anything other than apply blame to the entity attempting to financially manipulate retirement accounts into lining their own pockets.
4. Yes, there are other insiders with shares. I used a simplified example where there is a single insider, the founder, to highlight the power that the insiders have over the pricing in such a squeeze. However, you also got this wrong because insiders usually have lockup periods after the IPO that are longer than the 15-days expected for index inclusion. As such, the fund managers would not be able to purchase any shares other than the public shares until after the first rebalance.
by Veserv
3/16/2026 at 10:36:28 AM
I don’t think Nasdaq is free float based.Also, I would be a lot more pessimistic of the index tracking fund managers’ ability or willingness to find extra shares: their goal is to match the index, not beat it. If the index includes the new firm at a blown-up price because everyone sent their buy orders at the same closing auction, then all the index-tracking funds still track their underlying index. They do not care that after that closing auction, the price of the new firm—and likely the index itself—is going to drop.
by rokobobo
3/16/2026 at 11:28:41 AM
>I don’t think Nasdaq is free float based.I recommend the NDX proposal from February which the whole discussion is based upon:
"To balance index integrity and investability, Nasdaq proposes a new approach for including and weighting low-float securities (those below 20% free float). Each low-float security’s weight will be adjusted to five times its free float percentage, capped at 100%. Securities with more than 20% free float will continue to be weighted at full, eligible listed market capitalization, while those below 20% free float will be weighted proportionally to preserve investability."
The document includes a scenario with the rules applied to SpaceX. "Company C" in the table is SpaceX (with some estimated numbers).
https://indexes.nasdaqomx.com/docs/NDX_Consultation-February...
by super256