What patents reveal, once they stop mattering legally
A patent record is a timestamp with a business story attached: what a company bet on, when they stopped paying to protect it, and what that timing says in hindsight.
US11170444
The New York Stock Exchange itself filed a trade-quality-indication patent in 2021 — and let it lapse for nonpayment four years later, with fifteen years of possible term still ahead of it.
US8285619
An NLP-for-market-prediction patent from the bag-of-words era, filed in 2002 by a group of notable language-processing researchers. Its owner let it lapse for unpaid fees around 2024 — years before its adjusted term would have ended, and right as large language models made 'read the news, trade the sentiment' mainstream.
US3946218
The oldest grave in the corpus: a Hewlett-Packard calculator patent from 1974, for a machine that could compute a bond's yield to maturity at the push of a button — a genuinely novel thing to put in someone's hands, fifty years ago.
US4346442 & US4376978
Merrill Lynch's Cash Management Account — the product that first swept brokerage cash into money-market funds and let you write checks against your portfolio — patented twice, three months apart, in 1980.
The 10 oldest graves in the corpus
By grant date. The bottom of the timeline — yield-to-maturity on a calculator, before there was an internet to check it against.
| Patent | Title | Assignee | Granted | Term end (est.) |
|---|---|---|---|---|
| US3946218 | General purpose calculator with capability for performing yi | Hewlett-Packard Company, L.P. | 1976-03-23 | 1994-10-10 |
| US4334270 | Securities valuation system | — | 1982-06-08 | 1999-06-08 |
| US4346442 | Securities brokerage-cash management system | Merrill, Lynch, Pierce, Fenner & Smith | 1982-08-24 | 2000-07-29 |
| US4376978 | Securities brokerage-cash management system | Merrill, Lynch, Pierce, Fenner & Smith | 1983-03-15 | 2000-10-22 |
| US4412287 | Automated stock exchange | — | 1983-10-25 | 2002-09-15 |
| US4473824 | Price quotation system | Nelson B. Hunter | 1984-09-25 | 2003-07-22 |
| US4486853 | Apparatus for receiving and displaying continuously updated | Telemet American, Inc. | 1984-12-04 | 2001-12-04 |
| US4525779 | Conversational video system | Reuters Limited | 1985-06-25 | 2003-03-30 |
| US4532509 | Communication system having timer controlled field stations | Federal Signal Corporation | 1985-07-30 | 2002-07-30 |
| US4566066 | Securities valuation system | — | 1986-01-21 | 2003-01-21 |
Frequently asked questions
What kind of stories are these?
Each one uses a real patent record — its filing date, assignee, and lapse or expiry — as a lens on a business or technology decision, read in hindsight now that the patent no longer matters legally.
Do the dates here reflect legal patent status?
They're estimates computed from public filings, not legal determinations, and they ignore adjustments, extensions, and terminal disclaimers. Confirm against USPTO records before relying on any specific date.
Can I use an invention from an expired or lapsed patent?
Generally yes — once a patent's term ends or it lapses for non-payment, its claimed invention is public domain. Separate copyrights, trademarks, or other patents could still apply, so this is general information, not legal advice.