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SIGIL (SIJ-il), from the Latin sigillum, a seal.

Say it once.
It stays said.

A monitored message channel for co-parents whose court order calls for one. Each message is checked against your order before it goes. Once sent, it can't be edited or deleted in the app, and any change to the record is detectable.

Join the waitlist See how a record is checked
In developmentLaunching in Connecticut first.

What SIGIL does

Calm on a phone. Exact on the record.

SIGIL is a monitored communication channel for high-conflict family matters. It helps keep the conversation to the case, and keeps one honest record for both sides.

Messages that stay put

Sent messages can't be edited or deleted in the app. Sent and first-viewed times are kept, with subjects, threads and attachments, the same for both of you.

A check before you send

Automated screening checks each message against your order's terms. You see what it found and decide what to do. You remain responsible for what you send.

A record anyone with a receipt can check

Every message is chained to the one before it, and signed checkpoints go to both parties and a neutral custodian. Only fingerprints are checked. Your words are never published.

Read-only for the court and professionals

Judges receive message reports with the verification printed on the page. GALs, parenting coordinators, mediators and attorneys can be given read-only access.

A check before you send

Keep it to the case. Keep it on the record.

Before a message goes, automated screening by a large language model reads it against the communication terms in your order. It flags potential issues for human review. It never decides anything about you.

  • Not sent

    If a message may include language your order does not allow, or may relay contact to a person your order protects, SIGIL holds it back. Nothing is saved.

  • Your decision

    If a message may be off-topic, you can edit it, or add the case reason and send.

  • Just for you

    Optional style tips. Private, never saved, never shared.

Screening is automated and can be wrong. You remain responsible for what you send.

The record

Every message, fastened to the last

SIGIL keeps an append-only log. Each message carries a fingerprint of the one before it, so changing or removing one breaks every link after it.

  1. Chained

    Every message is hash-chained to the one before it, in the order it was sent.

  2. Checkpointed

    On a regular schedule, SIGIL signs a checkpoint: one short fingerprint for the whole record so far.

  3. Held by others

    Signed checkpoints go to both parties and a neutral custodian, so SIGIL can't quietly rewrite history.

  4. Anchored

    Checkpoints are timestamped by independent timestamp authorities and anchored to the Bitcoin blockchain through OpenTimestamps. Only fingerprints are anchored, never content.

How three messages become one checkpointDEMO
  1. M-00000511:30 AM
    Did the field trip form come home?
    e2df 7df8 … cf93 887d
  2. M-00000612:48 PM
    It's signed and in E.'s blue folder.
    c9ac cbea … d89b a3ac
  3. M-0000072:40 PM
    Got it. Reminder: the recital is Thursday at 6.
    c764 3c20 … 94ab 5ffb
  4. CHECKPOINT 000421 · 3:00 PM · SIGNED
Both partiesEach gets the same signed checkpoint.
A neutral custodianHolds a copy SIGIL can't take back.
Timestamp authoritiesIndependent services confirm the time.
OpenTimestampsAnchored to Bitcoin. Fingerprints only.

A wax seal never stopped anyone from opening a letter. It showed whether someone had.

SIGIL takes its name from the sigillum, the small seal pressed into wax to close a letter. The record works the same way: it doesn't claim nothing can change. It makes any change detectable. Read how the record is kept

Check a record

Proof you can check, not proof you have to trust.

You write it. SIGIL keeps it. Anyone with the receipt can check it. Only fingerprints are checked. Your words are never published.

Try it on a sample record made for this page. The check runs in your browser, the same way it will for a clerk, an attorney or either parent.

Open the full check
Not checked yet
Press "Check the sample record". It takes a moment.

This receipt checks the record. It does not judge what the message says, and it does not show who typed it.

RECORDDEMO export · 7 messages
CHECKPOINT000421 · 2026-10-03 19:00:00Z
ROOT6967 5694 … 6a64 f9ad
RESULTNot checked yet

Fairness

Two sides. One record.

The same words for both parents

Every prompt, label and notice reads the same for both of you. SIGIL doesn't take sides, and never says anything about a person.

The same record for both parents

You both see the same messages, times and checkpoints. Neither of you can change them, and neither can SIGIL without it showing.

Fair, plain-language terms

Terms written to be read in one sitting. They are in draft and will be published before launch. Read the plain-language terms

Who it's for

For everyone who reads the record

Parents

A calmer way to handle pickups, schedules and school forms when an order says it has to be in writing.

For families

Attorneys

A channel you can recommend or stipulate to, with reports that use the labels courts already read.

For attorneys

GALs, parenting coordinators and mediators

Read-only for the case. You see the record. You can't change it. Every view is logged.

For neutrals

Courts and clerks

Paper that explains itself, with the verification printed on the page.

For courts

Waitlist

Join the waitlist

SIGIL is in development and launching in Connecticut first. Tell us who you are, and SIGIL will write before it opens.

  • One email when SIGIL opens where you are. No marketing list.
  • Professionals: an early look at reports, read-only access and sample order language.
  • Parents: nothing to install yet, and nothing to pay.
I am

SIGIL uses what you enter only to write to you about SIGIL. Please don't include anything about your case.

The AVOWAL family

One family. Each shows its work.

AVOWAL is the platform. APPARITOR puts service of process on the record. SIGIL keeps the messages. One grammar, three inks.

AVOWAL

The platform.Legal operations. Independent licensed attorneys and ELARIA. avowal.ai

APPARITOR

The officer serves. We prove it.Service of process by licensed officers, on the record.

SIGIL

Say it once. It stays said.A monitored channel for co-parents. In development.