If company A has a subsidiary b and no goodwill, that means company A, sometime in the past, acquired what was then an independent company b (or possibly a “division” b that used to belong to some other company).
That was then.
Now, as far as IFRS is concerned, Ab is a consolidated whole and no longer (unlike under many “national GAAPs”) two separate and distinct legal entities.
Thus, there are only two ways that, under IFRS, subsidiary b can later be “merged” with some other entity.
One, it can be sold to company C.
In this case, it is no longer part of the Ab consolidated group and its capital structure is no longer of any concern to A.
Two, A can acquire another subsidiary (c).
In this case, if A paid more for c than c’s net assets, goodwill would arise. If A then decided to “merge” b and c into a single cash generating unit (or consider them a group of cash generating units) per IAS 36.80, the goodwill generated during the acquisition of c would be allocated to cash generating unit bc.
What you seem to be, on the other hand, suggesting is that no external acquisition(s) occurred and company A simply reorganized its own internal structure.
For example, A “merged” subsidiary b (a separate legal entity) to another subsidiary (also a separate legal entity) leading to a “change in capital structure” and “goodwill” as per the accounting legislation (“national GAAP”) mandatory in most countries (ex USA / UK).
The problem is, from an IFRS perspective, these legalistic considerations are irrelevant.
Therefore, it is not even possible to cite paragraphs that would, under IFRS, tell you how to do something that, from an IFRS perspective, cannot be done.
I am not saying that these operations would not have any impact on the IFRS report.
If, for example, this “change in capital structure” altered the consolidated group’s tax obligations, ability to pay out dividends, ability to repurchase stock, etc., IFRS would require disclosure of these facts.
What I am saying is that while formal, legalistically driven changes in capital structure are very common at entities required to (in addition to IFRS) apply “national GAAP”, they are not consistent with the way IFRS approaches financial reporting.
Or, put another way. Since, unlike legislated standards, IFRS applies to the consolidated group (the parent plus all its subsidiaries and all the subsidiaries’ subsidiaries and all the subsidiaries’ subsidiaries’ subsidiaries, etc.) regardless of legal structure , the issues you seem to be concerned with have nothing at all to do with IFRS (but I already said that in my first post).
Then again, since your description is the exact opposite of clear and complete, I may have misunderstood the issues.
If so, please provide a clear, step-by-step description of the transactions you are trying to recognize (as per IFRS) and I’ll try to make heads and tails of them.
BTW, it this “goodwill” was generated by an intra-group “merger”, this would be in direct violation of IAS 38.48, which states: Internally generated goodwill shall not be recognised as an asset.