Before attempting this question. You should know something.
The Steem Blockchain is decentralised and as such there is no need for the Conventional KYC that is done elsewhere. Therefore it is almost impossible if not impossible to know who the richest investor is.
A user can have different stakes on different accounts serving different functions. All those need to be added to get the real figure for that user.
You should also note that at the beginning it was possible to mine steem. Now the big question is between those that mine steem and those that bought, who are the real Investors.
Either ways, the richest investor on the platform for me is @ned. He still has his stakes on the platform. You may argue that since he's the CEO, someone else should be picked and not him. Well, we have seen CEO of other coins selling their stakes.
So many ways to interpret this question:
- The Richest Investor on Steemit or Steem the blockchain?
- The Richest overall or just considering the STEEM stake?
- The biggest SP holder or the richest as in net worth?
Too vague to answer in the right way, but @zoneboy answered well given the circumstances.