Set a clear limit to the parent brand
Shared ownership does not require a shared brand. The Google and Alphabet example illustrates a practical test: does an acquired business reinforce the established brand's central proposition, or make that proposition harder to understand? The commentary presents Google as keeping acquired brands separate and grouping home-grown projects under Alphabet, while largely reserving the Google name for activities that help consumers search or help advertisers capitalise on search behaviour. Its contrast with Yahoo! is about clarity: diversification can leave people unsure what a brand represents. Apply that distinction when considering an acquisition's identity. A business can belong to the group without carrying the established name if that name would become less meaningful as a result.
Sources: Strategy is complex, but winning brands keep it simple