They've publicly said that they won't invest when there are conflicts, e.g. Instagram and Picplz https://www.quora.com/Why-did-Andressen-Horowitz-invest-in-Pic

They've publicly said that they won't invest when there are conflicts, e.g. Instagram and Picplz https://www.quora.com/Why-did-Andressen-Horowitz-invest-in-PicPlz-when-they-were-already-investors-in-Instagram/answer/Marc-Andreessen https://www.quora.com/Why-did-Andressen-Horowitz-invest-in-P...