A very quick google would have given your the answer:
Ethereum creator Vitalik Buterin has proposed an answer to one of Ethereums more common questions whether or not the cryptocurrencys coin supply should ever be capped. In an Ethereum Improvement Proposal (EIP) on April 1st, Buterin wrote:
I recommend setting MAX_SUPPLY = 120,204,432, or exactly 2x the amount of ETH sold in the original ether sale.
It was a joke on April 1, but after many people supported this idea, he said that he seriously thought over it