Wagner Matching Engine
An automated futures-matching exchange, filed in November 1983 — one of the earliest attempts to put a human trading pit inside a computer.
Automated futures trading exchange · World Energy Exchange Corporation · filed 1983-11-03 · granted 1990-02-20 · expired 2007-02-20
Playable, self-contained demo. Nothing is sent anywhere; it runs entirely in your browser.
The story
Two origin stories share this neighborhood. US4903201 was filed November 3, 1983 by World Energy Exchange Corporation, describing an automated futures exchange — a matching engine standing in for the pit. It's remembered, when it's remembered at all, by the name attached to the litigation that followed: Wagner. History kept the lawsuit and mostly forgot the inventor.
Six weeks earlier, on September 15, 1982, an unassigned application was filed for US4412287, 'Automated stock exchange,' granted October 25, 1983 — before Wagner's filing even went in. Two independent attempts, within about a year of each other, to do the same essential thing: take the trading floor and put it in a machine. Both are free now. US4412287 lapsed on a missed maintenance fee in 1987; Wagner's ran its full term and expired in 2007.
The demo below rebuilds the matching-engine core the 1983 filing describes: orders in, priority and time rules applied, a match out. Play with the order book. Nothing here needs a license anymore.
Sources & further reading
Frequently asked questions
Can I use an expired or public-domain patent?
Once a patent's term ends or it lapses for non-payment, the invention it claimed generally enters the public domain and can be made, used, or sold without a license from the former owner. Separate copyrights, trademarks, or other patents may still apply to a specific product. This is general information, not legal advice.
Is an estimated date the same as a legal ruling?
No. Dates here are computed from public filing data and can differ from a patent's real status in either direction. Confirm against USPTO records before relying on one.
What does a maintenance-fee lapse mean?
US patents require maintenance fees at 3.5, 7.5, and 11.5 years after grant. If the owner stops paying, the patent lapses early and the invention enters the public domain years before its term would otherwise end.