The best recommendation is to collaborate through multi-workspace channels. The scenario requires long-term collaboration across departments that sit in different workspaces, including finance and legal, while keeping the acquisition private. Multi-workspace channels are designed for this Enterprise Grid pattern because they allow a channel to exist across selected workspaces without forcing every participant into a new workspace or duplicating conversations across separate channels. The channel can be private, tightly scoped, and available only to the required participants from each relevant workspace. Option A creates a separate hidden workspace, but that is heavier than necessary and can isolate work from the departments’ existing collaboration context. Option C introduces public channels for acquisition work, which is inappropriate because the acquisition is confidential. Option D puts everything in a global workspace, which risks over-centralizing sensitive work and may not align with the departments’ existing workspaces. Multi-workspace channels preserve confidentiality while supporting cross-functional collaboration in place.

Reference topic: Grid Design — multi-workspace channels, confidential cross-functional collaboration, private channel design, and Enterprise Grid workspace architecture.

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