# OPS-144 — Do not rotate domains across a bulk send

> Multiple fully-qualified domains, or multiple public URL shorteners, must not be cycled across bulk messages carrying similar content.

- **Rule ID:** OPS-144
- **Layer:** Operational (`OPERATIONAL`)
- **Checks:** `domains used across a bulk send`
- **Severity:** BLOCKING — Breaking this rule gets the submission rejected outright.
- **When it bites:** Falls due after approval, once you are live and sending
- **How it is detected:** Not knowable before submission — reported with its deadline
- **Fix type:** Hard stop — not remediable, resubmission will not help
- **Required by:** T-Mobile, AT&T, CTIA
- **Applies:** Applies to every 10DLC registration.
- **Canonical URL:** https://ekas.io/rules/10dlc/operational/ops-144/

## Why this rule exists

URL rotation is the content-side twin of snowshoeing: the domain is what a filter scores, so spreading one campaign across several defeats the scoring in exactly the way the numbers version does. The innocent case is per-channel tracking domains, which is a reasonable analytics decision that produces an identical fingerprint.

## How to fix it

Use one branded domain you control for every link in a campaign, and carry tracking in the path or the query rather than in the hostname.

## Check this yourself

**Does your marketing platform issue a different link domain per campaign or per channel?**

1. Look at the links in two recent campaigns and compare the hostnames. Several platforms rotate automatically, and the pattern is indistinguishable from deliberate evasion.
2. Use one branded domain you control for every link.
3. Carry tracking in the path or the query string rather than in the hostname.

*What wrong looks like:* Per-channel tracking domains are a reasonable analytics decision that produces exactly the fingerprint of URL rotation — the content-side twin of snowshoeing.

## Notes

Absorbs MSG-109, the same detection stated from the message-content side. Visible only across a real send. What the user has to check is whether their marketing platform issues per-campaign or per-channel domains automatically — several do, and the resulting pattern is indistinguishable from deliberate rotation.