[octaane]

Not possible according to the laws of physics. The closest you can get is a solar sail, but that's not "propellant-less" - photons are the propellant.

If a company thinks they've broken one of the most fundamental laws of physics (momentum transfer), they need to provide some serious evidence, and publish in full so their results can be replicated. A press release on an obscure website isn't how you do it.

[api]

Anyone publishing a repeatable experiment demonstrating this would be more or less instantly handed a nobel prize, since it would have to unlock new fundamental physics.

It would also totally rock cosmology since you’d have to rework the whole age and evolution of the universe in light of those new physics, whatever they were.

This is almost definitely bunk. Either that or something mundane explained in a ridiculous hypey way.

[GolfPopper]

It certainly sounds like "We managed to run our EM drive hardware in space, and our instruments say it did something" (as did EM drive proponent's, in error). Because if it really was even something like "we successfully produced thrust from ambient ions/earth's magnetic field/etc" then it would be much bigger news.

[K0balt]

Seems like the focus is on orbital dynamics, so I’m guessing it is reacting against the magnetic field of the planet or the particulates in the solosphere.

It would be cool, though, if it were actually interacting with the zero point field or some similar bunky stuff. We can already extract minute amounts of matter from the field, ostensibly experimentally proven, so I suppose it’s not impossible to imagine that you might somehow be able to push on Casimir forces, perhaps.