Short answer: it depends on your firm, and the only reliable source is your firm. This page explains what the rule usually turns on, so you can read your own firm's wording and understand what you're looking at.
Why there's no single answer
Prop firms write their own rules and change them. Some permit copying freely across accounts you own. Some permit it with conditions — often a cap on how many accounts, or a requirement that every account trades the same direction. Some prohibit it. A few say nothing clear at all, which is its own problem.
What almost every firm actually cares about is the same underlying thing: whether the firm is taking on a position it didn't price. One trader running their own strategy on their own accounts is a different risk from a signal service pushing trades into hundreds of strangers' accounts. Rules that look arbitrary usually make sense once you read them as a firm managing that exposure.
The distinction that catches people out
Copying across accounts you own is the common case and the one most firms address directly.
Copying from someone else's account into yours is a different activity. Firms that permit the first often prohibit the second. If you're following a signal provider, read the rule for that rather than assuming the copying rule covers it.
The second distinction, which catches people out more
Copying and automating are two different permissions, and firms treat them differently.
Some firms permit a trade copier but require written authorization before you run a bot, an EA or an algorithm. Others have no copy-trading rule at all but prohibit third-party automated trading systems outright. A platform like this one does both things, which means you can be compliant on one and not the other at the same firm.
So when you check, check twice. "Can I copy across my accounts?" and "Can I automate my entry?" are separate questions with separate answers.
How to find your firm's actual rule
Look for the firm's own rules page, FAQ, or terms. Not a Discord message, not a screenshotted support reply, and not a vendor's comparison table — including ours. Search the page for copy, copier, duplicate, multiple accounts, automated, bot and algorithm.
If the answer is ambiguous, ask the firm in writing and keep the reply. An ambiguous rule that you've asked about in writing is a much better position than an ambiguous rule you interpreted yourself.
Why we don't publish a table of this
We used to plan one. We decided against it, and the reasoning is worth knowing because it applies to every other vendor's table too.
Firms change their rules without telling vendors. A table that was accurate when it was written becomes wrong silently, and the trader relying on it finds out at the worst possible moment. A verification date helps, but it only tells you when someone last looked — not whether anything changed yesterday.
We'd rather point you at the firm than have you bet a funded account on our reading of their page.
What a copier does and doesn't change
A copier doesn't create a violation on its own. It places the same orders you'd place by hand, on more accounts. If your firm permits copying, using a tool to do it isn't a separate offense. If your firm prohibits it, doing it by hand isn't a loophole.
What a copier changes is scale. A mistake that costs you one account by hand costs you the group.
Before you build a group
Read your firm's rule and save a copy with the date. Check whether it caps account count. Check whether it treats demo and funded accounts differently. Check the automation rule separately from the copying rule. And start small, because the failure mode you're protecting against is the one you haven't thought of.
This is a reference, not advice, and it is not a statement about any firm's rules.