I wouldn't read too much into which molds were shown on the websites at certain dates as 'available to the public'.
At certain times decisions were made like only offering those molds which would be in production within a specific time period (attempting to have fixed schedules for each mold).
Also in the earlier days chips were made on other molds not shown for various reasons:
1. Awaiting clarification of ownership of some of the 'inherited' molds. (In some cases it took years for supposed original owners to be tracked down)
2. Molds owned by others could be used subject to a 'per chip' fee. (that's how the Elephant & Crown works now)
3. Molds pulled from use for repair might not have been shown again until someone actually asked for them.

Also very hard to track history for some molds described as 'open'.
Scenarios like Distributor A paid for it but was happy for B & C to order chips from it for a fee.
Some time later A sold it to B, or A maybe went bust and Burt were ok'd to treat is as abandoned and keep it, or it was purchased by Burt.

Of the 19 molds we list now, as far as I know:
10 were 'inherited from Burt' as open molds
2 were purchased by ASM
6 were purchased by CPC
1 (Elephant & Crown) used 'under licence'

There were a number of other inherited or purchased molds which were worn out and donated to Nevada Historical Society 6 years ago
(from memory HHL, DISQSQ, L, SMKEY, THUNDERBIRD, TRICLUB, TRIDENT, WREATH, TRIANGLE, CARO, TRIHEART)

Interesting situation when we bought out ASM Vegas. They held 3 molds that were not owned by them and should probably not have ever left Maine.
DIESWIRL, FLOWERS, ELEPHANT & CROWN
When contacted, Midwest demanded immediate return of the DIESWIRL (got shipped from Vegas direct without even coming back to me).
George & Co said they wanted us to continue to store the FLOWER mold as they didn't know what they wanted to do with it (still in the safe now) and NO, we could not use it, not even for a fee.
Marion & Co said we could use the ELEPHANT and pay them per chip made.