1/ @eriz35 asked a good question last week on why Tesla never seemed to trade down on bad news pre-market. I think the answer is: because no one real is actually trading this stock.
2/ Top 20 shareholders in $TSLA control 80% of shs out (using 169mm as denominator – real float prob closer to 145mm). In contrast, AMZN Top 20 control only 50%.
3/ For perspective, in past 9 mos. ended 12/31/17, cumulatively, Top 20 in Tesla have traded a grand total of only 13.8mm shares. Fido (seller) and TRowe (buyer) are 60% of that vol. Total Tesla shares traded over that same time frame? 1.17 bil.
4/ So, Top 20 holders have been only 1.11% of total Tesla volume since 4/20/17. Not wholly abnormal as AMZN Top 20 was also only 0.8% since 4/20/17. But. . .
5/ In the past year ended 4/20/17, Tesla traded 1.7 bil shares, more than 10x its shs out. For same period AMZN traded 630mm shares, only 1.3x shares out. Qtr just ended? Same ratio for both.
6/ What about evil shorty? For 9 mos ended 12/31/17, the short ratio in Tesla actually declined and only really spiked in March 2018. I said spiked, but that is a misnomer, as short interest is only now back up to highs reached previously.
7/ Short interest only increased recently and only by 3.4mil shares and mostly occurred during the two weeks between 3/15-3/31. But that 3.4mil shares were only 3.3% of total shares traded during that two-week period. So evil shorty is a rounding error in the day to day drama. 
8/ So where is this volume coming from in Tesla? Dealers and momo day traders just ping-ponging shares back and forth.
9/ Options volume in this name is Yuuuge (for good reason). If they are smart, derivative dealer desks aren’t carrying any shares to hedge with, and so use open market purchases and sales to delta hedge when necessary.
10/ For the past nine months (probably 12 when the 1Q18 13F’s are all released), AMZN clearly has been under accumulation. Tesla has not.
11/ So Tesla has a very high concentration of shares held in Top 20 hands as compared to many bellweather names. But it trades 5x more than average stock, and Top 20 doesn’t participate. It’s not widely held in ETF’s (for good reason).
I think the moral here is ignore the noise. Means nothing. Given the concentration in a few large hands, if the bough breaks, this implodes in spectacular fashion.
