Gemini vs Vertex AI: compliance comparison for Google buyers

TL;DR. Workspace Gemini and Vertex AI both run on Google's Gemini model family, but the compliance pictures diverge sharply. Workspace Gemini is a tenant-bound office-productivity feature inside an existing Google Workspace contract. Vertex AI is a Google Cloud developer platform with granular region selection, customer-managed encryption keys, BAA on eligible services, and a Model Garden that includes Anthropic, Meta, Mistral, and other third-party models as subprocessors. Workspace Gemini fits office productivity; Vertex AI fits product builds and regulated workflows.

The two surfaces

The shared underlying technology is Google's Gemini model family. The product wrapper, contract, and compliance surface around it differs.

The Workspace Gemini read sits at the Google Gemini profile. Vertex AI does not yet have its own CompanyScope profile; the comparison below covers the buyer-side compliance read.

Workspace Gemini

• Bundled into Google Workspace plans (Business Standard, Business Plus, Enterprise Standard, Enterprise Plus)
• Operates inside the buyer's existing Workspace tenant
• Customer data lives in the buyer's Workspace storage
• Contract is the Workspace Customer Agreement plus the Cloud Data Processing Addendum

Vertex AI

• A Google Cloud product the buyer subscribes to separately
• Operates inside the buyer's Google Cloud project, with project-scoped IAM and VPC controls
• Customer data lives in Google Cloud Storage, BigQuery, or wherever the buyer pipes it
• Contract is the Google Cloud Master Services Agreement plus the Cloud Data Processing Addendum, with the Vertex AI service-specific terms layered on

How the two compare

1. Tenant model and where customer data sits

| | Workspace Gemini | Vertex AI | |---|---|---| | Data location | Buyer's Workspace tenant (mail, drive, chat, meet, docs) | Buyer's Google Cloud project; explicit region selection | | Region selection | Workspace data residency on eligible plans | Per-service region selection at the resource level | | Customer-managed encryption keys (CMEK) | Available on Enterprise Plus for in-scope services | Available on most Vertex AI services | | VPC Service Controls | Workspace integration limited | Yes — VPC SC perimeter applicable to Vertex AI |

Vertex AI provides the granular controls regulated buyers usually need (CMEK, VPC SC, region pinning at the resource level). Workspace Gemini provides the simpler office-productivity wrapper that does not need them for most deployments.

2. Training default and the Model Garden question

| | Workspace Gemini | Vertex AI | |---|---|---| | Use of customer content to train Google base models | No | No | | Tenant-scoped fine-tuning | Limited | Available — Vertex AI Tuning, customer-scoped | | Third-party models available | N/A | Yes — Model Garden hosts Anthropic Claude, Meta Llama, Mistral, and others | | Third-party model use of customer content | N/A | Governed by Vertex AI's contract; the third-party model provider does not separately receive customer data | | Buyer responsibility for third-party model choice | N/A | Yes — Model Garden picks add the third-party model provider as a subprocessor under Vertex AI's terms |

The Model Garden is the structural Vertex AI difference. A buyer who picks Claude or Llama through Vertex AI gets that model under Vertex AI's contract, not directly from Anthropic or Meta. The third-party model provider sits as a subprocessor under Vertex AI's DPA, which simplifies the buyer's contracting but expands the subprocessor list.

3. HIPAA BAA position

| | Workspace Gemini | Vertex AI | |---|---|---| | BAA available | Yes — Google Workspace BAA covers Workspace Gemini for Healthcare and Life Sciences customers on eligible plans | Yes — Google Cloud BAA covers in-scope Vertex AI services | | Tier required | Eligible Workspace plan | Google Cloud project with BAA executed | | Consumer / free tier | No BAA | No BAA | | Eligible services | Specific Workspace Gemini features in scope | Specific Vertex AI services in scope; not all Model Garden models are HIPAA-eligible — confirm by service |

The Model Garden BAA picture needs the buyer to confirm by service. A third-party model offered through Vertex AI may or may not be in HIPAA scope depending on the underlying provider's own posture. The Vertex AI sales channel is the reliable source.

4. EU/UK transfer mechanism

| | Workspace Gemini | Vertex AI | |---|---|---| | SCC version | 2021 Module 2 | 2021 Module 2 | | UK Addendum | Yes | Yes | | Region commitment | Workspace data residency on Enterprise Plus | Per-resource region pinning at deployment time | | Sovereign cloud option | N/A within Workspace | Assured Workloads for regulated and public-sector buyers | | TIA depth required | Standard | Higher — Model Garden picks expand the subprocessor diagram |

5. AI Act deployer-side read

Both products are GPAI provider deployments under the EU AI Act when Google is the vendor. The deployer obligations land on the buyer based on use case:

• Workspace Gemini for office productivity (drafting emails, summarising meetings, document search) sits minimal-risk or transparency-tier.
• Vertex AI used to build a customer-facing chatbot, an automated screening tool, or a clinical decision-support feature can put the buyer into Annex III high-risk territory.
• Vertex AI Model Garden picks that include Anthropic or Meta GPAI models inherit those models' GPAI documentation; the buyer's deployer assessment uses the documentation Vertex AI publishes plus the model provider's published material.

See the EU AI Act hub for the deployer assessment workflow.

6. Subprocessor depth

| | Workspace Gemini | Vertex AI | |---|---|---| | Foundation model provider | Google (first-party) | Google + optional third-party models from the Model Garden (Anthropic, Meta, Mistral, others) | | Cloud subprocessor | Google Cloud (first-party) | Google Cloud (first-party) | | Third-party connector ecosystem | Workspace add-ons (controlled at tenant) | Vertex AI Extensions, Agent Builder integrations | | TIA documentation depth | Shorter | Longer — list every Model Garden model the buyer's app actually invokes |

Picking between them

Pick Workspace Gemini when:

• The use case is office productivity inside an existing Google Workspace tenant
• The buyer wants tenant-bound defaults without additional Google Cloud subscription, project structure, or developer overhead
• The compliance frame is minimal-risk or transparency-tier under the AI Act

Pick Vertex AI when:

• The buyer is building a product, an internal tool, or a regulated-industry workflow on top of Gemini or another model
• The deployment needs region pinning, CMEK, VPC Service Controls, or sovereign-cloud assurance
• The HIPAA BAA scope needs to be controlled at the Google Cloud project level, with the buyer choosing which services are in scope
• The buyer wants the Model Garden choice (Claude, Llama, Mistral) under one Google Cloud contract rather than direct vendor contracts

Run them in parallel when:

• Workspace Gemini covers the office-productivity layer for staff
• Vertex AI covers the production AI surface the buyer ships to customers or uses in regulated workflows
• The compliance owner manages two distinct deployer assessments because the use cases differ

The Model Garden expands the subprocessor map

The single biggest compliance-side consideration when picking Vertex AI is the Model Garden subprocessor expansion. Each third-party model the buyer's app invokes is a subprocessor under Vertex AI's contract. The Transfer Impact Assessment needs to list them; the AI Act deployer assessment needs to reference each model provider's GPAI documentation; the HIPAA BAA scope needs to confirm each model is in scope where PHI is involved.

This is manageable — Google handles the contracting upstream so the buyer does not need separate Anthropic or Meta contracts — but the buyer's documentation has to track the choices.

Related reading

• The DPA hub: DPA for AI vendors
• The AI Act deployer-side read: EU AI Act for AI buyers
• The HIPAA-specific checklist: HIPAA for AI tools
• Cross-comparison: Copilot 365 vs Google Workspace AI compliance
• Cross-comparison: OpenAI vs Anthropic DPA (because Vertex AI Model Garden offers Anthropic models as well)

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