Stamp Counts/Discoveries

Aside from the Siegel census are there any ways to determine how many sheets of a particular stamp are out there. Specifically, trying to track stamp types related to Scott listed errors. Trying to see if I can personally research and validate dealer stated scarcity/rarity levels. For instance how does one go about checking the statement "only one discovered sheet"? I do realize noone knows if a 2nd sheet may be out there, but how does one assert the claim in the first place?

Siegal is good but they dont have everything just items that are certified through various companies and there sales, There are still a lot that is not registered so you have to go by how many were made take away all registered ones that are out there. Its almost impossible to know if more will be discovered so they base it all off sales over the time they were made.They also use the company records that made the stamps, they destroy some and so on.The experts are about 98% right on most to 100% on rare stamps.I myself just went through a process of trying to find out if any 319fj types have ever been registered on cover, Seigal said they thought so, but I was un able to find any in there data base. I got a cert for it but still am unclear if any do exist other then mine on cover. Ill find out in the future I guess lol Good luck with your quest.

Here's another way to look at it:

The post office issued 100 un-inverted Jenny sheets. So far only 32 sheets have been reported to post office, and the registration info was included with the sheet, and had no additional cost.

Who knows what happened to the rest. They may be in collections. They may be on envelopes in some file drawer. They may be destroyed.

The same could be true for any error issued by the post office.

Those sheets are probably in the hands of smart collectors. Would you alert the world (and the IRS) that you bought a sheet for $12 that now might bring $45,000? I know that I would not have done so.
On the other hand, legitimate errors are less likely to suddenly increase in any appreciable quantity, they are usually too well known. An example might increase from one sheet to two but probably not ten, and there is enough of a market to absorb a few new examples. If an error is common it's usually known quickly. That has generally been the history of errors all along.

This then begs the question, how are the dealers getting so many of the full error sheets. My best guess, is that a select few have inside tracks within USPS. Also they must barter heavily to get the material. There are 2-3 dealers on eBay that have seemingly 75% of the error market cornered. The hobby has a lot of manipulation and

All the legit wheeling and dealing in the world won't land you the equivlant of Powerball odds hitting a 50-100 totally error sheet out of a few hundred million stamps offered. Yes naive people who come across stamps will let them go, but I suspect dealers have to acquire them from face up to 20% max SCV for there to be any room associated with the first rounds of markup. Then once the supply is generally shared, a valuation is assigned based on demand and quantity outstanding.

I wonder if you buy a PB error of a 1/50, essentially a 1 of a kind, and you set the price at $20k, will it essentially pin it to 5k as a going rate. Probably not because, it will be compared to an invert like cia/nyse and be pegged accordingly to a 25% of that. Its clearly not as desirable as an invert. So it's more like 5k PB with an ask of 1250. Me thinks it works something along these lines, where it's all scalable starting from the premium material prices on downward.

It's also true that those few dealers are known to have a serious interest in this type of material. So anyone who has anything interesting is going to approach them first. Errors are like any other philatelic area, some will always be much more popular then others, and some will always have the great story to go with it. Visual appeal is as important as rarity.

Pfsearch.org cert searches can be helpful too. Gives you an idea what might be out there by surveying what folks got reviewed.

Reminds me of error expert Jacques Schiff. RIP