A few companies like 9gag and Vayable did YC and 500 the accelerator, but others are just YC companies with 500 as an investor. E.g., you see 500/Techstars cro

A few companies like 9gag and Vayable did YC and 500 the accelerator, but others are just YC companies with 500 as an investor. E.g., you see 500/Techstars crossovers in the list. There are zero YC/Techstars crossovers because both are accelerators only unlike 500. Both YC and Techstars companies view themselves as having gone to the best accelerator program and it's expensive from an equity standpoint to do multiple accelerators, so it makes sense that there is zero overlap there.