Privacy Policy
ProtoJoint AI ("we") runs ProtoJoint at https://protojoint.ai. This policy says what personal information we collect, why, who we share it with, and the choices and rights you have. The person responsible for privacy at ProtoJoint can be reached at support@protojoint.ai.
Your designs
The CAD runs in your browser, and your designs are saved on your own device. Our servers receive them in two cases: when you use an AI feature - the AI chat (the conversation, a summary of the open design, and pictures of it the AI asks for) or an AI app you connect to your account (the tool calls it makes and their results), which we pass to our AI provider to produce the answers - and when they are contributed to improve ProtoJoint's AI, as the next section says. We keep a record of each AI request's size and cost for billing.
Contributing to ProtoJoint's AI
ProtoJoint's AI is built on a model from Anthropic; we do not train language models. We improve how ProtoJoint uses it - the instructions it is given, its tools, the checks on what it builds - by testing it on real design work. That work comes from contributions:
- Designs: what you model - a design's sketches, features, parameters, components and joints - and the names of the editor's actions that made it (such as "extrude" or "undo"; not what you type). Not included: the contents of files you import (STEP, .sldprt, meshes) and pictures you lay on a plane; they stay on your device.
- AI sessions, from contributors only: your conversations with the built-in AI (what you write, the pictures you send, its answers and the steps it takes) and the tool calls of AI apps you connect, with their results.
Who contributes what. On the free plan, signed in or not, the designs you make are contributed unless you turn that off - in Account › Privacy, or with the note at the foot of the editor when you are signed out. Contributing your AI sessions too is your choice; it gives a free account AI credits and MCP calls each month. On a paid plan nothing is contributed unless you choose to contribute your designs and AI sessions, at the plan's lower contributor's price. In the European Union, the European Economic Area, the United Kingdom, Switzerland and Quebec nothing is contributed until you say so.
How it is kept. Under a random identifier, not your name or email address, and with no IP address. Only we use it, to test and improve ProtoJoint's AI; we do not sell it, publish it or give it to anyone, and Anthropic does not train its models on what our servers send it. Contributions are kept for up to five years.
Changing your mind. Turn contributing off at any time; nothing more is collected from then on. You can delete everything you contributed (Account › Privacy, or signed out with the editor's data dialog), and deleting your account deletes it too. What a contribution already helped improve - an instruction we changed, a test built from it - stays improved.
Notice of financial incentive. The contributor's price (about a fifth below each plan's other price) and a free account's monthly AI credits and MCP calls are offered in exchange for contributing designs and AI sessions. You take part by choosing to contribute, and stop by turning it off in Account › Privacy: a paid plan then renews at its other price, and a free account keeps the CAD without the monthly AI credits. We estimate a contributor's data is worth at least the difference to us - $3 to $20 a month, by plan - because building comparable tests from paid modelling work would cost us more than that.
What we collect
- Account: your email address, an optional name, a hash of your password (never the password itself), your language, the invitation code you used, your consent choices, the spending limits you set, and - only if you tell us at sign-up - how you heard about ProtoJoint.
- Billing: your plan and its status, credits and their use, invoices and payments. Link, the merchant-of-record service of Stripe, takes the payments; we do not receive your full card number. We keep a fingerprint Stripe gives for a card (not the card number), or the email address of the Link account you paid with, to apply one free trial per card and to stop referral abuse.
- Usage and security: IP address, browser and device type, sign-in times, the AI model and tools used, the credits they cost and the month's MCP calls, and a security log of account events (sign-ins, password changes, your choices about contributing).
- Page statistics: Cloudflare Web Analytics counts visits to the pages of our website and editor and measures how fast they load and respond: the page's address, the site that linked to it, your country, browser, operating system and device type, and the page's timings. It uses no cookies or browser storage and does not fingerprint you, so it cannot tell who you are or follow you from site to site.
- Contributions to ProtoJoint's AI, as described above.
- Messages you send us, and the waitlist note if you leave one. Feedback you send from ProtoJoint or our website: what you write, the address you leave for an answer (your account's when you are signed in), the page it was sent from, your IP address and browser, and - only if you tick the box - a summary of the open design: how many features, bodies and components it has, its units, your browser and screen size. That summary has no geometry and no names.
Why we use it
To provide your account and the features you ask for; to bill you and prevent fraud and abuse (for example one trial per customer, limits on sign-ups and AI use); to keep the Service secure; to see which pages are visited and keep them fast; to send you the emails the Service needs (confirmations, password resets, receipts, notices about your plan and credits); to answer you; to meet legal obligations; to test and improve ProtoJoint's AI with contributions; and, only if you opted in, to send you product news. You can opt out of product news at any time.
Who we share it with
We do not sell your personal information or share it for targeted advertising. We share it only with service providers that work for us, under contracts that limit their use of it:
- Stripe (payment processing), Anthropic (the AI model behind the AI features), our email provider (sending email), Cloudflare (DNS, network protection, the bot check on sign-up, page statistics, and the off-site copy of our backups), and our hosting provider.
- Link, Stripe's merchant-of-record service, which sells you a plan or a credit pack: it receives your name, email address, billing address and payment details to take the payment, work out the tax and send your receipts, under its own privacy policy.
- Authorities, when the law requires it, and a buyer of our business, under this policy.
Your information may be processed in the United States and Canada, and wherever these providers operate.
Cookies
We use one essential cookie to keep you signed in, and your browser's storage for your preferences (such as language), for your choice about contributing designs and, signed out, a random identifier for this browser's contributions (so that you can delete them). Cloudflare's bot check may use its own cookies when it runs; its page statistics use none. We do not use advertising or tracking cookies.
How long we keep it
Account information until you delete your account; database backups for up to 14 days after that. Payment and tax records as long as the law requires (they are held by Stripe and Link). Usage totals without your identity may be kept for accounting. Card fingerprints are kept to apply the one-trial rule. Contributions are kept for up to five years, and deleted sooner when you ask or delete your account. Feedback is kept as long as it helps us improve ProtoJoint; when you delete your account, your address, IP address and browser are removed from the feedback you sent.
Your choices and rights
- In Account settings you can see and correct your information, download your data, change your consents, turn contributing on or off, delete what you contributed and delete your account.
- Depending on where you live (for example California and other US states, or Canada and Quebec), you may have rights to know, access, correct, delete and port your personal information, to withdraw consent, and to appeal our decision. Write to support@protojoint.ai; we answer within the time the law sets and will not treat you differently for using these rights. The contributor's price is the one difference, and it follows a choice you make.
- You can complain to your privacy regulator (for example the Office of the Privacy Commissioner of Canada).
Security
We use encryption in transit, hashed passwords, short-lived and revocable tokens, and limited access to our systems. No method is perfect; if a breach affects you, we will tell you as the law requires.
Children
ProtoJoint is not for children under 13, and we do not knowingly collect their information. If you believe a child has given us information, write to us and we will delete it.
Changes
We will post changes here and tell you of material ones by email or in the app before they apply.