That's a curious device. I would be interested to see what's really inside the package, it looks like MOSFETs but also needs a power source. With 10V VDS maximum and a 500 Ohm on resistance it's market must be somewhat limited.
Hi Brian,
You're right, looks like very low voltage oscillators seems it's main use (I searched IEEE), e.g. power harvesting I suppose. In one example, they paralleled 24 of them to increase the transconductance.