Many companies have right of first refusal on any private share transfers. You need to offer the shares back to the company at whatever sales price you agreed t

Many companies have right of first refusal on any private share transfers. You need to offer the shares back to the company at whatever sales price you agreed to with a third party. Most times, the company can just sit on the offer and never actually respond. There are no timeliness clauses or guarantees when evaluating the offer. Notoriously, this happens with companies like Uber. If you were friends with Travis, you could sell. If not, you'll go pound sand. Investors also want to see the books and numbers. Not everyone can sell on hype alone. Even leaked numbers from Uber were taken with huge grains of salt. Over the counter arrangements and warrants are on dubious legal standings with regards to transfer-controlled private "stock units". Actual shares are a different story, but everyone gives out "stock units" and not shares. It might seem pedantic, but there's a gulf of difference while the company is still private.