What’s New
For the period July 9, 2025, through July 15, 2025, there are 13 newly-issued inbred patents, and 16 newly-issued hybrid patents.
There are 3 newly-expired inbred patents, and 1 newly-expired hybrid patent.
The number of US-issued corn inbred and hybrid patents per decade has risen dramatically from:
Decade Inbred Patents Hybrid Patents Inbred Patents Hybrid Patents
Issued Issued Expired Expired
- 1986-1995 80 8 13 0
- 1996-2005 591 167 28 8
- 2006-2015 1538 1377 145 25
- 2016-current 1449 1689 774 683
May 13, 2025, a significant number of inbreds have had 2 or even 3 patents issued for them. In such cases, the patents are identified with a (1of2) or (2of2) following the name of the inbred, eg. – ABC357(1of2). In these cases, the patent office requires a Terminal Disclosure Notice to be printed in the final PDF version of the patent. This statement indicates that the subsequent patents expire no later than the 1st or original patent. Consequently, inbreds with multiple patents issued to them may have expiration dates earlier that originally assigned by CPIS. As of May 13, 2025, all new (correct) expiration dates reflect the change imposed by the Terminal Disclosure Notice. Previously, the expiration dates assigned by CPIS to 2nd or 3rd patents had NOT reflected the Terminal Disclosure rule.
April 24, 2025, Certain changes have been made for many patent expiration dates after May 28, 2020. These changes have been made as a result of changes in patent law which now post a time extension of “x number of days” as determined by the United States Patent and Trademark Office (USPTO). This extension is applied to the usual 20-year patent duration from the date the patent was filed with USPTO, and varies from 0 to “x” number of days depending on the patent. The previous USPTO rule provided 20 years of protection from the patent FILING DATE, OR, 17 years of protection from the patent ISSUE DATE if the time between the patent FILING DATE and the patent ISSUE DATE was MORE THAN 3 YEARS. For the time being, both the old (obsolete) expiration dates as well as the new (correct) expiration dates will be provided on all search pages that report patent expiration dates. Please note that PVP (Plant Variety Protection) Certificate expiration dates are NOT affect by this change in patent law.
Dec 28, 2022, Two features have been added to the search options for EXPIRED INBRED PATENTS, EXPIRED INBRED PVPs, and INBRED GENETIC SEARCHES. Specifically, the number of patented progeny, AND the number of patented hybrids derived from inbreds are now listed along side the inbreds in the results page as well as the details page. This feature may provide information on the relative value of individual inbred lines within a patent assignee’s breeding program.
Dec 14, 2022, When searching in the “Inbred Genetic Backgrounds or Offspring” search, the report now indicates whether the patent or PVP certificates of an inbred or its resulting offspring inbreds have expired. The result is either “YES” (expired) or “NO” (not expired).
Dec 14, 2022, “Inbred Patents Expired or Soon to Expire” and “Inbred PVP Certificates Expired or Soon to Expire” now also allow for the search of individual inbreds to see if they are expired. Enter the name of the inbred in the “Inbred” field. If the inbred patent or PVP is expired, a result will be returned to the summary and details pages. If the inbred patent or PVP is not expired, no results will be returned.
Aug 3, 2022, During the Aug 2, 2022, database update, some difficulties were encountered with the format of certain date values, causing problems with certain data searches as well as search results. Any information generated from searches from Aug 2 – Aug 3, 2022, was correct. However, some information normally expected from the search may have been missing. The issues underlying this problem were identified and resolved, and the database as well as search functions used after Aug 3, 2022, are once again working properly. CPIS apologizes for any inconvenience created during the Aug 2 – Aug 3 time period, and thanks you for your patience.
July 24, 2019, “Other ID 1” field has been added to the Results pages of “New Inbreds Patented in the Last 28 Days” and “New Inbreds PVP-Certified in the Last 6 Months”. This field is listed adjacent to the “Inbred Variety” field.
Feb 6, 2019, “Other ID 1” field has been added to the Results pages of “Inbred Patents Expired or Soon to Expire”, “Inbred PVP Certificates Expired or Soon to Expire”, and “Inbred Pedigree Genetic Background Search”. This field is listed adjacent to the “Inbred Variety” field.
Starting Nov 27, 2018, the details pages pertaining to various inbred information searches now lists Grand Parents (2nd previous breeding cycle) of each inbred listed on the Report page.
On Mar 27, 2018, about 60 older, publicly-developed “founder” inbred lines were added to the database for more comprehensive ancestry search, even though these founder lines were never patented nor PVP-protected. This list of founder lines includes inbreds such as A632, B14, B73, C103, MO17, OH43, etc. The pedigrees of these founder lines were graciously provided with permission to publish by MBS Genetics, LLC, Ames, IA, USA.
On Dec 13, 2017, a new page was added to the web site, titled “Obtaining Seed”. This page provides general information regarding how to obtain seed samples of patented and/or PVP-certified maize germplasm. This page is not intended as an exhaustive list of ways in which to obtain seed. However, it does provide some of the more common options.
There are currently over 700 patented corn inbreds for which PVP certificates have not been issued, and over 600 PVP-certified corn inbreds for which patents have not been issued.
CPIS has, through the month of September, 2016, updated our entire database in order to account for any patented corn germplasm for which patent maintenance fees were not paid, and which therefore have expired due to maintenance fee neglect according to the US Patent and Trademark Office. As of Oct 4, 2016, this database update reflects 25 corn inbred varieties and 16 corn hybrid varieties for which patents had expired prematurely due to non-payment of patent maintenance fees. These database updates are now henceforth reflected in any patent expiration date queries made. Maintenance fee non-payment activities will henceforth be monitored, and will reflect in the ongoing weekly database updates. To see if a particular patent has expired due to non-payment of maintenance fees, please check the Details page for an expired variety. If an expired variety has a date listed for “Abandoned_Maintenance_Fee”, the patent was expired on the date listed.