Currently, 03-09-2018, the Bitcoin price increasing but Market Cap is the same. What does this mean ?
Does it mean few people or group buy bitcoins?
it is not possible.
I think that the only thing you can possibly be referring to is the WHOLE market cap of altcoins+bitcoin and in this case , it is possible that btc is growing while alts are going down and the net market cap stay the same or even decreases.