"Hi madamswer, I realise every situation is different, but how...

"Hi madamswer, I realise every situation is different, but how long do you think the smaller less loved part of a demerger takes to reach a natural equilibrium state (i.e. for all of the forced holders to exit). For what it is worth a few of the examples I have looked at seem to take a few weeks up to about 6 months."

It's really hard to be even remotely accurate about this sort of thing; in my experience, it usually takes more than just a few days, but less than a few months (bit of a nothing answer, I know).

What I estimate, judging from the schedule of distribution of shareholders (which was derived from the WFD register), is that around 50%-55% of OMN's register of some 94m shares is comprised of institutional investors, and around one-third is retail investors (Recall that Unibail-Rodamco holds an escrowed 10% stake.)

I suspect that most of those institutional investors would be very large (multi-billion dollar funds), and by far the majority of them would be either benchmark-aware funds, international funds or income funds, which would have been the reasons they held WFD.
Needless to say, there is zero reason for them to own OMN.

So I think its fair to say that the majority of the 50m shares owned by investment institutions will need to be absorbed by the market. In addition, if one assumes that, maybe, one-quarter of retail shareholders will be net sellers (and most of these will commence in the new financial year, I'll wager), that will represent a further 10m shares.

So, by my (admittedly crude) estimates, the overhang of OMN stock when it listed was around 60m shares. Which is a lot, in the context of the 94m shares in issue.

The good news is that, since it debuted trading some 9 days ago, around 35m of OMN stock has been transacted.

So, those with an inclination to sell, certainly appear to be getting on with it, so much so that it looks like it might already be halfway done.

Of course, the pace of forced selling could slow naturally from here, so it might take twice or three times as long for the market to digest the remaining selling.

So, maybe another month, or maybe six weeks of it, still to go?

But, as you can tell, I'm making all sorts of libertine assumptions in my...uh... "analysis", so take it with the pinch of salt as is surely warranted.
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