Cross your own flow, inside the spread.
The Darkpools internalizer is a deterministic matching engine for banks and broker-dealers. It crosses eligible client orders against internal liquidity at the midpoint of the prevailing NBBO, before they reach a public venue.
How a match happens
Every order follows the same deterministic path, from receipt to execution report.
An internalizer lets an institution match its clients’ buy and sell interest against each other before anything is routed to a public venue. Orders that can be crossed internally are filled without being displayed, so large institutional interest does not signal intent to the market.
The Darkpools engine executes at the midpoint: the price halfway between the national best bid and offer. Buyer and seller each receive price improvement against the displayed quote, and the whole decision is reproducible, because the same inputs always produce the same sequence of outcomes.
Every step is recorded, so each execution can be replayed later for surveillance, dispute resolution or a best-execution review.
Order received
FIX session from the client desk or order management system
Pre-trade risk cleared
Credit, limits and restricted-list checks
Midpoint computed
Reference price pegged to the NBBO midpoint
Internal cross matched
Eligible buy and sell interest crossed in price-time priority
Execution report issued
Sent to the client, to compliance and to settlement
What the engine does
The matching capabilities an internalizer needs, in one engine.
Midpoint and pegged matching
NBBO-referenced midpoint plus primary and market pegs, with a configurable offset per client.
Complete order-type coverage
IOC, FOK, minimum-quantity and conditional orders, all handled under strict price-time priority.
Deterministic sequencing
A single-writer engine with reproducible sequencing, so every execution can be replayed exactly.
Pre-trade risk and kill-switch
Per-client credit and limit checks, with instantaneous halt at desk or firm level.
Native connectivity
FIX 4.2–5.0 for order routing and drop-copy, plus documented REST and streaming APIs.
Replayable for surveillance
The full order lifecycle can be replayed for market-abuse monitoring and examiner requests.
Why institutions internalize
Matching client flow internally changes who sees it, and who benefits from the spread.
Less information leakage
Orders crossed internally are not displayed, so size and intent stay inside your venue.
Price improvement at the midpoint
Both sides trade inside the spread instead of crossing it, which is the point of midpoint matching.
Control over your own flow
You decide which orders and counterparties are eligible, and the rules that govern them.
Evidence for best execution
Every decision is recorded in a form that can be replayed and explained on request.
| Side | Price | Qty | Book |
|---|---|---|---|
| Ask | 241.150 | 15,400 | displayed |
| Mid | 241.135 | 15,000 | matched |
| Bid | 241.120 | 14,100 | non-displayed |
Prices are illustrative. In the example, the buyer pays 0.015 less than the offer and the seller receives 0.015 more than the bid.
Specifications
The internalizer at a glance.
Common questions
About the internalizer.
What is an internalizer?
In this context, it is a matching engine that lets a bank or broker-dealer cross client orders against internal liquidity before routing anything to a public venue. The Darkpools internalizer does this at the NBBO midpoint under strict price-time priority.
What does midpoint matching mean?
A midpoint match executes at the price halfway between the national best bid and the national best offer. The buyer pays less than the offer and the seller receives more than the bid, so both sides improve on the displayed quote.
Does Darkpools operate a dark pool?
No. Darkpools is a technology provider. Our clients operate their own venues under their own regulatory permissions. Darkpools is not a broker-dealer, exchange or ATS operator.
Is this the same as a systematic internaliser?
Not necessarily. “Systematic internaliser” is a regulatory status under MiFID II for firms that deal on own account against client orders on an organised, frequent, systematic and substantial basis. Whether your firm falls into that category depends on your activity and jurisdiction. The platform captures the data the regime requires, but the classification is your firm’s to determine.
Can it connect to our existing order management system?
Orders arrive over standard FIX, so most order and execution management systems can connect through configuration. We scope the details with you in a technical briefing.
What happens after a trade is matched?
The execution report goes to the client, to compliance and to the Darkpools settlement platform automatically, so the trade continues on one path to delivery-versus-payment.
Talk to the team that builds it.
Briefings are run by our engineers. Tell us about your desk and we will arrange a time.
We only contact clients from @darkpools.co addresses. See our official channels.