Keppler KIC 8462852

My best guess is that these types of odd variation will be found in about 0.01% of stars who had or have planetary companions. I think the perhaps the rotation of the star surface is what we are seeing. The dips are because some large planetary object(s) have collided with this star and we are seeing the 'thermal shadow' of cooler material on the suns surface which is yet to ignite or disperse through the sun. Such collisions also affect the rotation speed of the suns surface if struck at an oblique angle the surface of the star can appear to rotate much faster than the main mass of the star. Over thousands of years the new surface material will heat up and the surface (heloitic atmosphere) spin will gradually slow as rotational momentum is passed to the star's core through drag. This is my best guess.