From all I've heard and read over the past several years, some is fact, some rumor, and some is certainly conjecture:
Seville Enterprises leased the tooling from John Hanle, founder of Jo-Han.
Hanle apparently misrepresented the condition of the tooling, what actually existed as to complete tooling, and Seville also found out that the Jo-Han molds only fit in Jo-Han's ancient molding machines, (a rumor at the time was that AMT had passed on the tooling for just that reason, & it's known that Revell/Monogram looked into it).
This was a major blow to Seville's plans, as they wanted to use the Jo-Han molds to reduce down time in their own molding machines, Hanle was looking at selling way back in 1979, several years before this actually happened.
From all the information that has been given over the past several years, a lot of the tooling had already "disappeared" when Hanle still owned it.
Seville sued Jo-Han/Hanle over the misrepresentation, this was a long and drawn out lawsuit eventually settled in Seville's favor, giving them sole ownership of Jo-Han, but it was rumored that the punitive damages amounted to $1.00, which didn't cover lawyer's fees for Seville.
During all of this, even more tooling "disappeared", leaving many tools forever gone or missing so many vital parts that they couldn't be brought back...
Apparently Seville was unable to do any injection molding due to tooling being missing, and what few Jo-Han kits that were released during their ownership of JoHan were pieced together from test shots, existing stock and the like.
Imagine, what kind of mess the company was left in once Hanle got older, but I have read stories about him sleeping in his office either to try to thwart theft, or because he was reduced to that due to financial issues.
Seville looks for someone to buy what few remaining assets there are.
Along comes Okey Spaulding from Kentucky, a good modeler. He gets the financing to purchase what's left.
IIRC, Okey ran Accucast which was doing resin casting of interiors for old Jo-Han promos and the like, and thus that's how he was privy to the fact it was up for sale.
Somehow after a physical inventory is done, more tooling "disappears" before it can be moved from Detroit to Kentucky...
Here's some information about just that copied word for word from the instruction sheet for the last issue of the 68 Plymouth police car:
"Welcome to the new Johan. When we purchased Jo-Han from the previous owner, we had some great plans for this kit-add a 6 cylinder engine, mold it in white, have clear glass & lenses, correct the deck lettering...etc. But, when the trucks arrived to move the tooling, this tool had "mysteriously" disappeared. While going through the arduous task of recovering the tool, we decided to do the best with what little we had. There were thousands of police car parts already molded, as well as thousands of the same old decals, green glass & incorrect instructions."There's more regarding that kit being pieced together from existing parts, but you get the basic idea of the condition of Johan from that above.
Now when this was done, reverse engineering already existed, so why didn't Okey look into doing that for the kit?
The main reason was money.
He's tried to run Johan as a 1 man operation for years now, contacting with Best Resin to make resin parts for missing or incorrect ones, that fell by the wayside even before the deaths of the owners of Best Resin.
He also got some assistance from R&D Unique as well, but he's basically been trying to resurrect a long gone company by himself.
It's been said as fact and also rumored, that people held a lot of Jo-Han tooling, (as well as historical artifacts such as company artwork & the like), due to past monies owed them by the previous owners, and that Okey knew it but didn't have the funds to acquire them himself, and much was sold off on ebay or traded hands in other ways.
Okey was shopping the remains of Johan around a few years ago, in vain hopes of finding a buyer, he does a few sales at swapmeets, and never tells anyone what is going on, what tooling physically exists, and of that what is complete...
Roughly 90-95% of the tooling is either missing or so incomplete that unless reverse engineering can be done affordably, and even then the tooling has to be adapted to fit the ancient molding machines in Okey's possession, that we are highly unlikely to see JoHan brought back in any sort of viable fashion.
There is no bringing JoHan back.
The cost of repairing and replacing the damaged and missing tooling, converting what does exist to work in more modern machines, along with other factors makes it prohibitively expensive.
Some molds still exist.
These include the AMX, SC Rambler, Sox and Martin Cuda, and the Mercury Comet Pro Stock and some early promo bodies.
Jo-han has released a few promos in the recent past. These include: the Chrysler Turbine, Rambler Station Wagon, and the Rambler Unibody Promo.
These were last released by Testor's.
All the tooling that Testors ran in the HSO series still exists, unfortunately Testors no longer is interested in doing any plastic kits...
Lindberg purchased all the kit tooling that Testors had, that was in usable condition but the deal did not include the old Jo-Han tooling due to their poor condition, they're still sitting in storage basically in Limbo...
As it is, I doubt we'll ever see any more models with the Jo-han branding...