Privacy Policy

Who we are

LinearZeta LLC is a Massachusetts limited liability company that builds and runs conversational AI voice agents for local service businesses. Based in Worcester, Massachusetts. You can reach us about anything in this policy at hello@linearzeta.com.

This policy covers three different situations: visiting this website, calling a business whose phone is answered by a voice agent we run, and being a LinearZeta client. They work differently, so we explain them separately.

1. If you visit this website

What we collect

• Email address — only if you give it to us, by subscribing to the newsletter or requesting your results from the missed-call calculator.
• Calculator inputs — if you use the missed-call calculator and submit your email, the figures you entered (call volume, missed-call rate, booking value) are saved with your email so we can follow up usefully. The calculator itself stores nothing on your device.
• Where you came from — if you arrive via a link with campaign tags (UTM parameters), we keep the first set in your browser's session storage. It is deleted when you close the tab and is only sent to us if you submit your email.
• Anonymous analytics — we use Cloudflare Web Analytics, which is cookieless. It does not track you across sites, fingerprint your device, or build a profile of you.

What we do with it

• Your email, the source (newsletter or calculator), any calculator figures, and campaign tags are kept as a single subscriber record in our newsletter and lead system. Every email includes an unsubscribe link that works.
• If you book a free call audit, scheduling is handled by our scheduling provider under its own privacy policy.

What we never do

• We do not sell or rent your data to anyone.
• We do not run advertising trackers or third-party ad cookies on this site.
• We do not email you unless you asked us to.

2. If you call a business that uses our voice agent

When you call a business whose phone is answered by a LinearZeta voice agent, we process your call on that business's behalf. The business decides why your data is collected; we handle it for them under this policy and our agreement with them.

You're told up front

Every call begins with a disclosure that you are speaking with an AI assistant and that the call is recorded. That disclosure is the first thing the agent says, on every call, without exception. If you'd rather not continue, you can ask for a person and the agent will transfer you.

What is collected on a call

• The call itself — audio and a transcript, processed through Twilio (telephony) and ElevenLabs (conversational AI), and retained for the business you called.
• What you tell the agent — typically your name, a callback number, and what you need (for example, an appointment request). The agent collects the minimum needed to handle your call.
• Booking details — if you book an appointment, your name, contact details, and requested time are passed to the business's own scheduling system so the appointment actually exists in their calendar.

Returning-caller recognition

• So the agent can say "welcome back" and avoid re-asking for details you've already given, we keep a small caller record (name, email if you provided it, preferences, last visit reason) for the business you called.
• Your phone number is never stored in readable form — the record is keyed on a one-way cryptographic hash of the number.
• Records are scoped to the one business you called. Calling a salon never lets a plumber's agent recognize you, or vice versa.
• Internal performance telemetry about bookings contains no personal information about you at all.

Health information

Our agents are not set up to handle protected health information, and we do not currently take on work that requires HIPAA-regulated data handling. Agents never give medical or clinical advice — anything clinical is routed to a person at the business.

Deletion on request

You can have your caller record deleted at any time: ask the business you called, or email hello@linearzeta.com with the business name and the phone number you called from. We delete the caller record and unlink your call history. Retention of recordings and transcripts follows the agreement with each business and applicable state law.

3. If you're a LinearZeta client

What you give us during onboarding

When we set up your voice agent, we collect your business contact details — your name, business name, email, and, if you want lead alerts and account notifications by text, a mobile number. We use these to run your service and to reach you about it. Nothing more.

SMS lead alerts & account notifications (LinearZeta Lead Alerts)

• We only text you with your express written consent, given on our opt-in page — never as part of signing up. The consent box is never pre-checked, and consent is not a condition of creating an account, purchasing, or using the service.
• You can revoke consent at any time: reply STOP to any message, reply HELP for help, or email hello@linearzeta.com. Lead alerts then switch to email.
• We keep a record of each opt-in (the number, the time, and where consent was given) for as long as you're subscribed, plus the period carriers require us to be able to prove consent.
• Message frequency varies with your call volume, and message and data rates may apply depending on your mobile plan.
• No mobile information will be shared with third parties or affiliates for marketing/promotional purposes. Your opt-in data and consent records are never sold or shared.

Full program terms are in our SMS Policy.

Sub-processors we rely on

We use a small, deliberate set of service providers ("sub-processors"), each of which processes data only to provide its service to us. This is the current list; we keep it up to date and note material changes by updating the effective date above.

• Twilio — telephony: carries the inbound phone calls our agents answer.
• ElevenLabs — conversational AI and speech processing: the voice agent itself, including speech-to-text transcription of calls.
• Cloudflare — hosting and CDN for this website, cookieless web analytics, and the infrastructure that runs our caller-memory and booking systems.
• Buttondown — our newsletter and lead system: stores the subscriber record (email, source, any calculator figures, campaign tags) and sends email.
• Cal.com — scheduling for the free call audit booked from this website.

If a business connects its own scheduling or intake system (for example, its existing appointment software), booking details go to that system under the business's own terms with that provider.

Your rights & choices

You can ask us what we hold about you, ask us to correct it, or ask us to delete it — email hello@linearzeta.com and we'll respond promptly. Depending on where you live (for example, under California, Colorado, Connecticut, Virginia, and other state privacy laws), these may also be legal rights; we honor them either way, and we won't discriminate against you for exercising them.

We do not sell your personal information, and we do not share it for cross-context behavioral advertising. Because there is nothing to opt out of on that front, we don't show a "Do Not Sell or Share My Personal Information" link.

Global Privacy Control (GPC). Some browsers and extensions let you broadcast a Global Privacy Control signal. We honor recognized GPC signals as a valid opt-out of any sale or sharing of personal information. Since we don't sell or share in the first place, there's nothing further you need to do — but if that ever changes, an active GPC signal is treated as your opt-out automatically.

If we change this policy, we'll update the effective date at the top. Material changes to how caller data is handled are also communicated to the businesses we serve.