Count the holdings described by the source
Ownership analysis begins with the scope of the document. It may identify initial subscribers, later reported shareholders, a controlling interest or an accounting parent, each answering a different question. Before producing a percentage or ownership diagram, identify the share class, voting rights and relevant date, and confirm that the source covers the whole population you intend to analyse.
Keep control and consolidation in separate columns
UK confirmation reporting can contain shareholder information, PSC guidance addresses significant control, and GLEIF relationship data concerns specified parent relationships. A company may appear in more than one of these systems with apparently different descriptions because the definitions differ. Explain those differences in your research notes instead of forcing every source into a single unsupported ownership hierarchy.