I can only guess at what the company would say but here goes
1. The patent number is and has been a part of the name & ID of the plant no need to change now. 2. the law does not REQUIRE me to tell you when the patent has expired. 3. if you pay me royalty money after the patent expires well..... I will return it if you ask for a refund..... again that is my guess.

The patent was filed for in 1983, and probably granted in 1986. However, the question is, did the patent office grant a temporary patent when it was filed, in 1983, to cover the time between filing and granting of the patent?

To be safe assume the patent ends in 2006.

Joseph, you are right. This plant patent expired on Nov. 21, 2003.

Like you said, a plant patent is good for 20 years from the application filing date. The 1986 date is probably when the patent was finally issued. Since it sometimes takes the patent examiners a long time to review an application and issue a patent, the government has tried to fix that problem by letting inventors count back to the date the inventor filed his or her patent application. I don't know if there is any rule against continuing to list the patent number after it expired. I doubt it. The government doesn't re-use the patent numbers. Sometimes plant patents can get re-issued (but it gets a new patent number assigned).

Trivia - the first patent examiner in the US was Thomas Jefferson (in 1790). The first plant to be patented was the "New Dawn" climbing rose w/ champagne blooms (in 1931).

i have read some where about that, but it also mention that there many small scale nursery out there whom can't afford to pay loyal fee, so they cheat. they can slightly hybrid the plant or they just re name the plant. that is why there some plants have more than one name, name change also make plants go off the shelf quicker.

Thank you all.

A plant patent is basically a patent on the 'genetic make up of a plant, it's 'genenode. If you have a seedling from that plant and it looks alot like the parent, the possibality of that seeding being identical to the parent is remote to nearly none. Therefore the seedling is not covered by the patent.

Patent lag time is not unusual, no mater what it is to be patented. That is why you can find patent applied for on items that span much more then 3 years. Especially on manufactured items, many times after being issued a patent, the item was still sent out with patent applied for on the product, merely because to retool the dye was expensive. SO trying to guess when a patent expired on those products is hard to do, unless you look up the product and determine when it was applied for and issued. Frankly i was unaware there was even patents on plants. Does that only apply to hybrids or also on previously undiscovered naturally grown plants. I would have thought you would just copyright the name as a new plant type, the original plant would of course been patented by God, with no expiration.

KCassidy, please, with reference to what you wrote re. a seedling of a patented plant, what about a sport the flowers of which are a completely different colour from the rest of the plant, do you know what is the position re. propagating this portion?

A sport can be patented separately. But the original patented name is still protected intellectual prperty.

This patent subject has some quirks.

I have Weigela 'Alexandra' now I see that some one changed the name to (aka Wine and Roses). I have seen this happen several times.

So whats the deal if its propagated and sold as 'Alexandra'? This name existed prior to Wine and Roses.

I think this situation is happening more often especially with plants from other countries being introduced into the US market. They seem to be marketed under new names for a new market. Old plant, new name.

I acknowledge new plants with protection but OLD plants, give me a brake.

Maybe I'll patent Dandelion "Yellow Lawn"

Ron