Probably from the Philippines

[RobT]

I find the notches at the base of the blade curious. Nothing in my admittedly small Philippine collection has this feature. Are they characteristic of Negrito blades? They look like they might be uncomfortable if the blade was used in a thrust. Were they put there to stop the hand from sliding up the blade? Are they be sufficiently large to do so? The blade also seems thinner at the spine than the typical Philippine knife and, on top of that, appears to have a fuller. Why so thin? Is this common in Negrito blades?