"Private" gets used for three different setups. Each one answers a different question: who can read the prompts, who decides how long they are kept, and whose hardware runs the model. For a firm of 10 to 200 people, the right kind depends on which of those questions your clients, insurers, and regulators actually ask.
See the workflow for how to move your team's ChatGPT use to company AI.
What does "private" mean for an AI chatbot?
In practice it means three separate things. No training: the provider keeps your prompts and files out of the data it uses to improve its models. Retention control: someone at your company decides how long conversations are kept and can delete them. Containment: prompts are processed only by companies you have a contract with, or by no outside company at all. A business plan of a public chatbot gives you the first and part of the second. Self-hosting gives you all three, at a price.
How do the three kinds of private AI chat compare?
| Business plan of a public chatbot | Company-administered chat app over model APIs | Self-hosted open-weights model |
|---|---|---|
| What it is | The work edition of a chatbot your staff already know, in a workspace your company owns | A chat app, built or bought, that your company administers and that sends prompts to one or more model APIs |
| Training on your data | Off by default on the major vendors' business plans | Off by default on the major model APIs |
| Who holds the prompts | The chatbot vendor | The app operator, plus the model provider, which commonly keeps API traffic up to 30 days for abuse checks |
| Retention control | Workspace admins on some plans; custom periods often reserved for enterprise tiers | Set by whoever administers the app |
| Admin and sign-in | Central billing, admin console, and single sign-on on business tiers | Whatever the app provides |
| Shared documents | Shared projects and connectors to email and file storage | Workspaces with their own document collections |
| Model choice | The vendor's own models | Any model the app connects to |
| Checks before the model | The vendor's own safety filters | Your rules, applied to each prompt before it leaves |
| Typical cost | About $20 to $25 a seat a month on the major vendors' standard business seats | App subscription plus model usage |
| Upkeep | The vendor runs everything | The app provider or your IT team runs the app |
If staff already use ChatGPT, Claude, or Copilot, is the work version private?
Each of the big vendors makes the same core commitment for its business editions, and each draws the line at the work account. ChatGPT: OpenAI says data from its business plans and API is excluded from model training by default, and on its Business plan workspace admins control how long data is kept and can view, export, and delete members' conversations. Claude: Anthropic's commercial terms state that it "may not train models on Customer Content from Services." Copilot Chat: Microsoft says prompts from staff signed in with a work account on an eligible Microsoft 365 plan fall under its Data Protection Addendum and stay out of foundation model training. Web search queries sent to Bing follow separate terms.
The protections belong to the work account. A client file pasted into someone's personal account falls under personal-plan terms, and Microsoft states that staff signed in with a personal account get none of the enterprise protections. A business plan also leaves two things to you: what staff paste in, and which rules apply to client data. Is ChatGPT safe to use at work? covers what each ChatGPT and Claude plan does with your data.
What does a company-administered AI chat add?
Your company decides who gets in, which documents each team can use, how long conversations are kept, and which rules each prompt is checked against before it leaves. The prompts still reach a model provider, so the provider's API terms apply underneath: the major APIs exclude traffic from training by default and keep it for up to 30 days for abuse monitoring, with zero data retention available to customers the provider approves. Ask the app provider which model APIs it uses and under which of those terms.
To add checks on each prompt without a new chat app, Sentinel is an AI gateway that reads each prompt on its way to a supported AI tool and replaces the identifiers it recognizes before the prompt leaves the computer. Raw prompts and responses stay in the customer's environment.
What is a self-hosted or on-premise LLM, and what does it cost?
A self-hosted model is an open-weights model downloaded and run on hardware you control, in your office or in your own cloud account. Prompts never reach an outside AI company. Several AI companies publish open-weights models, including some built for a single high-memory GPU. For what "open" covers, see What is the difference between open weights and open source?.
The cost is mostly GPU memory. Hugging Face's rule of thumb is about 2 GB of GPU memory per billion parameters at standard 16-bit precision, so a 70-billion-parameter model needs about 140 GB just to load. Compressing the model to 8 or 4 bits cuts that, with some change in answer quality. Modelled: a four-GPU cloud server with 192 GB of GPU memory, run around the clock at on-demand rates, comes to about $7,660 a month by our arithmetic from a public cloud price list dated October 7, 2026. That figure leaves out storage, backups, and the staff time to patch, monitor, and upgrade the model. Smaller models need less memory and cost less to run.
For most firms of 10 to 200 people, that arithmetic settles it. Self-hosting earns its cost when a contract or regulator requires prompts to stay on infrastructure you control.
What should you ask any private AI chat provider?
Whichever kind you pick, the same six questions sort a real commitment from a marketing line. Ask for each answer in writing.
- Where are conversations stored? Ask which company, which cloud, and which country holds them, including any model provider behind the app.
- For how long? Ask for the default retention period, who can change it, and how soon a deleted conversation leaves backups.
- Who can read them? Ask whether your admins, the provider's staff, or contractors can open a conversation, and for what reasons.
- Do they train a model? Ask whether prompts, files, or feedback ever feed any model, and whether that is off by default or only on request.
- What does the admin control? Ask about sign-in, user roles, document access, retention settings, logs, and checks on prompts before they leave.
- What does the contract say? Ask for the commercial terms and data processing addendum that make each answer above binding.
Start from your client contracts: if one names where data may be processed, that requirement picks the kind for you. To follow a prompt from the keyboard to the model and back, read Where does your data go when people use AI?.
Frequently asked questions
- Is there a private version of ChatGPT?
- OpenAI's business plans keep workspace data out of its model training by default and give admins control over retention and members' conversations. Conversations still sit on OpenAI's servers, so the vendor holds the data.
- What is a private LLM?
- A private LLM is a language model run so that only your organization sends it prompts and sees its answers. Most often it is an open-weights model hosted on your own servers or in your own cloud account.
- Can I run ChatGPT on my own servers?
- ChatGPT itself runs as OpenAI's hosted service. To keep prompts on your own hardware, you run an open-weights model, which several AI companies publish for anyone to download.
- Is Microsoft Copilot Chat private?
- For staff signed in with a work account on an eligible Microsoft 365 plan, Microsoft says prompts and responses fall under its Data Protection Addendum and stay out of foundation model training. Web search queries sent to Bing follow separate terms, and personal accounts get none of these protections.
- Do business AI chat plans train on company data?
- The major vendors say their business plans and APIs exclude customer content from model training by default. Ask whether feedback such as thumbs up or down counts as consent, and get the commitment in the contract.
- How much does a self-hosted LLM cost?
- Mostly GPU hardware and staff time. By our arithmetic, a four-GPU cloud server with enough memory for a 70-billion-parameter model costs about $7,660 a month at on-demand rates, before storage, backups, and the people who run it.
- What is the most secure AI chat for a small business?
- The one your staff use inside a company account, with retention set by your own admin, prompts checked against your rules, and contract terms behind each data commitment. A private tool that people bypass for their personal accounts protects nothing.
Keep going
Is ChatGPT safe to use at work?
Where does your data go when people use AI?
Take it into the vendor call
A practical next step
Sources
- OpenAI, Enterprise privacy at OpenAI (updated January 8, 2026), including the ChatGPT Business, API Platform, and model training FAQs. Read October 8, 2026.
- OpenAI, Business pricing. Read October 8, 2026.
- OpenAI API documentation, Data controls in the OpenAI platform. Read October 8, 2026.
- OpenAI, Introducing gpt-oss (August 5, 2025), an open-weights release sized for a single 80 GB GPU. Read October 8, 2026.
- Anthropic, Commercial Terms of Service (effective June 17, 2025). Read October 8, 2026.
- Anthropic Privacy Center, How long do you store my organization's data? Read October 8, 2026.
- Claude Help Center, Custom data retention controls for Claude Enterprise. Read October 8, 2026.
- Anthropic, Claude plans and pricing (Team and Enterprise). Read October 8, 2026.
- Microsoft Learn, Enterprise data protection in Microsoft Copilot and Microsoft Copilot Chat (updated May 29, 2026). Read October 8, 2026.
- Microsoft Learn, Manage Microsoft Copilot Chat (updated October 1, 2026). Read October 8, 2026.
- Hugging Face, Optimizing LLMs for speed and memory (Transformers documentation). Read October 8, 2026.
- Amazon Web Services, Amazon EC2 G6e instances (four-GPU, 192 GB configuration used in the modelled cost). Read October 8, 2026.
- Amazon Web Services, Amazon EC2 On-Demand pricing, Linux, US East (N. Virginia), price list published October 7, 2026: $10.49 an hour for g6e.12xlarge, times 730 hours. Read October 8, 2026.