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Hi, I am working on a project right now for an existing client, we have one domain up and running well, they want to create an 'umbrella' site to cover three current business divisions and roll everything up under that main site, including the existing site on a totally different domain (would migrate over and 301 redirect from current domain). From what I've researched, I am inclined towards one main domain with three sub-domains due to the amount of content for each business division being significantly different enough that it seems to deserve separation from each other. However, in terms of SEO and maintaining consistent domain authority, would anyone recommend it be better to structure this as just folders/categories falling under the main domain instead of separate sub-domains for each division, and focus keyword targeting on pages tailored to that end within the main domain structure rather than spreading out link-juice to different sub-domains? Thanks!