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Slack

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Panel rating · 6 judges · How to read the stars

Category median

Sovereignty: not determined

0–5 in half steps. 5 means the rubric's top anchor is met on the evidence.

by Salesforce, Inc. · slack.com

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Read this page as one judge. Each weighs the same scores by what they care about.

The Skeptic

Weighted verdict

Reads for the message-history cap, the tier where SSO appears, and what "unlimited" excludes. Has seen "end-to-end encrypted" mean direct messages only, on request, with search disabled — and wants that sentence found rather than assumed.

Same scores as the panel view — this lens weights them the way this judge cares.

Scored by The Skeptic

Channels, threads & search

How this is scored

The daily surface: channel model, threading, mentions, files, and whether search can find a decision made eighteen months ago.

0 — Flat group chats with no threads; search covers recent messages only, and history is capped.

3 — Channels and direct messages with basic search, but threading is awkward or absent and file handling is a plain attachment list.

5 — Public and private channels, real threads, mentions and reactions, file sharing with previews, and full-text search across the whole history.

8 — Cross-organisation or guest channels with clear boundaries, message editing history, pinned and saved items, search with filters by channel, person and date, and a documented history limit or none at all.

10 — The archive is a working knowledge base: search that ranks well across years, threads that stay readable, channel lifecycle management (archive, rename, merge) without losing history, and export of a conversation in a form a human can read.

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The Skeptic

Channels, Slack Connect cross-organisation rooms with admin-controlled connection policy, AI search over stored knowledge, and — credit where due — a legible history cap: one year on Free, unlimited from Pro. But the words 'thread', 'edit history', 'pinned' and any human-readable export of a conversation appear nowhere in this registry, so I stop short of the 8 anchor. 1 2 3 2

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Encryption & access control

How this is scored

What is encrypted and against whom, plus who can reach which room. Judged on documented mechanism, since "encrypted" in this category usually means the vendor holds the keys.

0 — Transport encryption only, undocumented; no role model beyond admin, guests indistinguishable from members.

3 — TLS and encryption at rest with vendor-held keys, basic roles, and guest access that mostly works.

5 — The above plus configurable roles per channel, SSO, guest accounts with scoped visibility, and a clear statement of what the vendor can read.

8 — Optional end-to-end encryption for direct messages or private rooms with the trade-offs named, device verification, session management an admin can revoke, and documented key handling.

10 — End-to-end encryption as a first-class mode — documented or open cryptography, cross-device key management that ordinary users survive, identity verification, and the vendor stating plainly what it cannot decrypt.

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The Skeptic

Encryption at rest and in transit with the vendor holding the keys, plus SAML SSO down to Free, 2FA, information barriers and an Enterprise Key Management add-on — key custody you can rent, not E2EE. There is no end-to-end encryption and no sentence stating what the vendor itself can read anywhere in the evidence, and silence on that is the finding. 1 2 2

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Retention, discovery & co-determination

How this is scored

The archive as a legal object: retention policies, export for discovery, audit, and the monitoring features a works council will ask to have switched off.

0 — No retention policy, no export beyond a manual copy, no audit log, and presence or activity analytics that cannot be disabled.

3 — Manual export of some data and a global history limit, but no per-channel retention, no audit log and no admin control over analytics.

5 — Configurable retention per channel or workspace, admin export in a documented format, an audit log of administrative actions, and status or presence that a user can control.

8 — Legal-hold and eDiscovery export including edits and deletions, retention executed per policy and evidenced, full admin audit trail, and activity analytics switchable off organisation-wide.

10 — Built to pass a works agreement and a subpoena on the same day: granular retention with documented deletion, discovery export a lawyer can use, complete audit, and no individual-level productivity scoring anywhere in the product.

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The Skeptic

Retention configurable at workspace and channel level (plan-dependent), legal hold, audit logs and native DLP on every plan — real governance bones. But no discovery or export format is documented in any form, and nothing says whether presence or activity analytics can be switched off — the archive as a legal object is half-built in this evidence. 2 3 2

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Deployment & data custody

How this is scored

Whether the customer can hold their own archive: self-hosting, private cloud, open source, federation, and what an exit actually looks like.

0 — Cloud-only, proprietary, with export limited to a partial archive.

3 — Cloud-only, but with a documented full export in an open-ish format.

5 — A private-cloud or dedicated-instance option, or a self-hosted edition that lags the cloud significantly; full export documented.

8 — A genuine self-hosted edition close to feature parity, or open-source core with a documented upgrade path, plus complete export including files and metadata.

10 — Custody is the customer's: open-source or source-available server, self-hosting supported as a first-class deployment, open protocol or federation, and a migration path in and out that the vendor documents rather than resists.

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The Skeptic

Cloud-only SaaS: the entire registry is tier pricing, and the one 'private cloud' sentence is Slack's own AWS private cloud for their LLMs, not a customer deployment option. No self-hosting, no open-source core, and no export path documented at all — even the anchor-3 bar of a documented full export goes unevidenced, and Germany residency from Business+ changes where the vendor holds your archive, not who holds it. 2 2

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Integrations & extensibility

How this is scored

Bots, webhooks, app framework, identity — whether the chat becomes the place work is noticed, and whether that is buildable without a partner agreement.

0 — No API, no webhooks, no bots.

3 — Incoming webhooks and a handful of native integrations; no bot framework, no documented limits.

5 — Documented REST API, incoming and outgoing webhooks, slash commands, a bot account model, and SSO.

8 — A proper app framework with interactive components, event subscriptions with retries, SCIM provisioning, documented rate limits and a sandbox.

10 — A platform: versioned API with a deprecation policy, an app directory or plugin system with permissions a customer can audit, and integrations the vendor maintains rather than lists.

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The Skeptic

Named integrations, 1.7 million weekly active apps, automation 'mit einem Klick oder per Code', SCIM provisioning, SSO, and per-workspace control over third-party services. What's missing for the next anchor: any documented API surface, rate limits, sandbox or deprecation policy — this sheet evidences an ecosystem, not a documented platform. 1 2 3 2

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European sovereignty

How this is scored

Where the archive and its metadata live, who the contracting entity is, which subprocessors touch it. Independently sourced by the sovereignty pipeline; scored here as this buyer weighs it.

0 — Non-EU vendor and contracting entity, hosting unstated or non-EU, subprocessors unnamed.

3 — EU data residency offered for message content while metadata, search indexes or support tooling remain non-EU, or the contracting entity sits outside the EU.

5 — EU hosting as standard and an EU contracting entity, but parts of the chain — notifications, AI features, analytics — are non-EU without an explained safeguard.

8 — EU hosting on named infrastructure, EU contracting entity, full subprocessor list published, any non-EU processing named with its legal basis.

10 — Sovereign end to end and evidenced: vendor, entity, hosting and every subprocessor European, certification published, and a self-hosted option that removes the question.

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The Skeptic

The vendor is Salesforce, Inc. of San Francisco, and the pipeline could confirm neither contracting entity, ownership, default residency nor a single subprocessor on the captured pages. The one European fact — 'Datenstandort Deutschland' — starts at Business+, making EU custody an upsell, and the LLMs sit in Slack's AWS private cloud of unstated region. 2 2

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Pricing transparency

How this is scored

Whether a buyer can compute the annual invoice for their headcount — including the retention, compliance and guest features they actually need — from public pages alone.

0 — No public prices at all; every tier is a sales conversation.

3 — A per-user headline exists, but the tier where retention control, SSO or compliance export begins is unstated.

5 — Per-user prices public with billing period stated, but at least one commonly needed capability (unlimited history, SSO, eDiscovery) sits in an unpriced enterprise tier.

8 — Every tier priced publicly with per-user maths, history and storage limits, feature boundaries, minimum term and VAT treatment stated; self-hosted licensing priced too where offered.

10 — Complete price computability: annual invoice derivable for a given headcount and deployment choice, including guest users, storage and any per-instance licence.

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The Skeptic

The tier boundaries are unusually legible — unlimited history from Pro, SAML SSO from Free, DLP on all plans, Germany residency from Business+, EKM as an add-on — but the registry contains not a single per-user price, billing period or VAT treatment. Without a number anywhere, the annual invoice is not computable from this evidence, so I score below the 'headline exists' anchor despite the good feature-to-tier mapping. 2 2

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European sovereignty — proven facts

0 of 4 dimensions proven

Built only from facts shown on the vendor's own pages. A dimension we could not prove is left open, not scored as zero.

Ownership Not determined ⚠ unverified — uncited Report an error
Data residency Not determined ⚠ unverified — uncited Report an error
Subprocessors Not determined ⚠ unverified — uncited Report an error

Where this could be wrong

What we left out

A claim that does not survive our checks costs us the claim, not the page. This is what was taken off this one.

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Sources (12)

The pages every claim on this page was read from — each one checked, dated, and kept verifiable.

  1. 1 Vendor homepage slack.com Checked 15 Sep 2026 Details →
  2. 2 Pricing slack.com Checked 15 Sep 2026 +1 earlier capture: 15 Sep 2026 Details →
  3. 3 Privacy policy slack.com Checked 15 Sep 2026 Details →
  4. 4 Legal notice slack.com Checked 21 Sep 2026 Details →
  5. 5 Channels, threads & search — found from sitemap slack.com Checked 1 Oct 2026 Details →
  6. 6 Channels, threads & search — found from sitemap slack.com Checked 1 Oct 2026 Details →
  7. 7 Encryption & access control — found from sitemap slack.com Checked 1 Oct 2026 Details →
  8. 8 Encryption & access control — found from sitemap slack.com Checked 1 Oct 2026 Details →
  9. 9 Retention, discovery & co-determination — found from sitemap slack.com Checked 1 Oct 2026 Details →
  10. 10 Retention, discovery & co-determination — found from sitemap slack.com Checked 1 Oct 2026 Details →
  11. 11 Integrations & extensibility — found from sitemap slack.com Checked 1 Oct 2026 Details →
  12. 12 Integrations & extensibility — found from sitemap slack.com Checked 1 Oct 2026 Details →