Emissive static lighting breaks with no "static shadow"

When using an emissive object as a lightsource for baked-lighting:

If the object is set to not cast a static shadow, it’s light is not baked. In the screenshot provided, both cubes have the same material; the difference being that the cube on the right has the option “static shadow” unchecked. Not sure where to go from here.

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Thank you Jon. I did discover that enabling “Shadow Indirect Only” on the light-casting object does seem to fix this issue. Not sure how it correlates with disabling static shadows, but it could be used as a work-around for some cases.

Hi kippernicus, I was able to reproduce this issue in UE versions 4.15, 4.16, 4.17, and 4.18. After consulting with a lighting expert, it appears that this is not actually a bug with the engine, but is working as intended.

Thank you for the update. Can you confirm that enabling “Shadow Indirect Only” on the light-casting object is the proper solution for this issue?

Yes, that is correct.