[JL2010]

I'm going to put my speculation hat on here. Others here have mentioned that the chip in question is an Actel FPGA.

First, we must understand what these are used in: embedded systems. Typically, at the heart of most embedded systems you have two possibilities: a microcontroller or microprocessor, or an FPGA. The microcomputers run some kind of firmware (instruction set fed to a processor architecture) which is completely different then an FPGA which are actually re-configurable transistor arrays to implement fixed digital logic. This transistor configuration is typically loaded from EEPROM on power up - so it is stored/uploaded by a user somewhere after they've done some work in their CAD tool.

In either case, whether it be firmware written for a microprocessor based system, or the "firmware" for an FPGA (I forget what that logic routing configuration format is called - technically not firmware since it's not instructions) it is likely that whoever wrote it would want to protect it from being read or protect their device from having another firmware loaded on. There are many schemes to do so, it is possible that this is what has been compromised.