Does LockRoom publish sending IP addresses?

No. LockRoom sends through Resend, which by default uses shared IP addresses spread across many senders. There is no fixed IP list to allowlist. Use the sending domains and DKIM instead.

Is LockRoom email authenticated?

Yes. lockroom.com publishes SPF, DKIM keys for Resend and Google Workspace, and a DMARC policy of p=quarantine. send.lockroom.com publishes its own SPF record.

Help

Email allowlist for LockRoom invites

For IT and security teams at firms invited into a LockRoom data room. What we send from, what to allowlist, and how our mail is authenticated.

Short version

Allowlist the sender support@lockroom.com and the domains lockroom.com and send.lockroom.com, and require DKIM or SPF to pass. LockRoom sends through Resend on shared IP addresses, so allowlist by domain, not by IP.

What to allowlist

Sender address: support@lockroom.com. Data room invites and notifications come from this address. The display name is the name of the firm that sent the invite, not LockRoom, and replies go to the person who invited you.
From domain: lockroom.com
Return-Path (envelope sender) domain: send.lockroom.com
DKIM: selector resend on lockroom.com (key published at resend._domainkey.lockroom.com)
Sending service: Resend

The safest rule is a sender allow for lockroom.com that also requires DKIM or SPF to pass. An allow on the domain alone, with no authentication check, would also let spoofed mail through.

Why not IP addresses

LockRoom sends through Resend. Per Resend's documentation, all Resend senders use shared IP addresses by default, a pool shared across many senders, and Resend does not expose the IPs even in dedicated pools because those pools scale dynamically. There is no fixed IP list we can give you. Allowlist by domain and DKIM.

How our mail is authenticated

These records are public and you can check them with any DNS lookup.

SPF for lockroom.com: v=spf1 include:_spf.google.com include:amazonses.com ~all
SPF for send.lockroom.com: v=spf1 include:amazonses.com ~all
DKIM: keys published at resend._domainkey.lockroom.com (application mail) and google._domainkey.lockroom.com (staff mail from Google Workspace)
DMARC for lockroom.com: p=quarantine

Forward this to IT

Bankers: if a buyer's invite did not arrive, send them this.

Copy and send

I have been invited to a LockRoom data room and the invite may be held by our email filter.
Please allowlist support@lockroom.com and the domains lockroom.com and send.lockroom.com (DKIM selector resend). Details: lockroom.com/help/email-allowlist

Still no invite?

Check spam, junk, and your organization's quarantine for mail from support@lockroom.com.
Once the allow rule is in place, ask the banker to resend the invite from the room. See how buyers are invited.
Security questions beyond email: how secure LockRoom is.
Anything else: email support@lockroom.com, or browse the LockRoom help index.