I'll try to better clarify some of this stuff based on what I know.

Archimedes started as the US distributor for IAR.

Franklin started as the US distributor for KEIL.

Around 1994, IAR decided to sell direct in the US and cancelled their contract with Archimedes. Archimedes started reselling KEIL C51 V5 in 1995 under the Archimedes name. The prior Archimedes tools (IAR V4) were not compatible with the new Archimedes tools (KEIL V5). As far as I know, there was no utility to automate the upgrade process. The Archimedes tools (KEIL V5) were 100% compatible with the KEIL V5 tools. No migration utility was required. In about 2001, Archimedes went out of business. KEIL took over support for customers with existing contracts.

Around 1994, KEIL decided to sell direct in the US. At that time, Franklin was an exclusive distributor and this contract was renegotiated. Franklin decided to drop the KEIL product line and acquire new products. The first round of new products were not as robust as the KEIL tools and were somewhat buggy from customer accounts. I'm pretty certain these were the Raisonance tools. Over time, bugs were corrected and new features added to make these tools as close as possible to the KEIL tools. In about 2001, Raisonance decided to sell direct in the US.

I do not know the disposition of Raisonance and Franklin. But, I am pretty certain that no one involved was sued.

Jon