So, to refresh these numbers, I sat down, reviewed various sources, and calculated:
164.19 million shares total
Here's the ones who will not sell any time soon:
33.63 million held by Musk (after the most recent conversions) -- down to 20.4%
Another roughly 0.5 million shares held by other insiders (mostly JB Straubel and Kimbal Musk)
5.85 million held by Fidelity Contrafund (ultrabullish, never sells)
0.70 million held by Fidelity Contrafund VIP (same management, I think)
4.42 million held by Fidelity OTC (ultrabullish, never sells)
(Other Fidelity funds may sell, see below)
13.29 million held by Bailie Gifford (decidedly bullish and long-term)
(T Rowe Price often sells, see below)
8.17 million held by Tencent (probably much more, since that was *exactly* 5% at the time of report; nobody ever stops buying just *over* the reporting threshold)
2.69 million held by Vanguard Total Stock Market Index (they have to add more as TSLA goes up)
1.54 million held by Vanguard Extended Market Index (they have to add more as TSLA goes up)
1.41 million held by other Vanguard funds (since they're mostly indexes, same thing for the cap-weighted indexes)
3.79 million at Morgan Stanley (MS is a consistent buyer and rarely sells -- Adam Jonas? -- though they sold a little recently)
3.31 million at Bank of Montreal (Also a consistent buyer and rarely sells, though they sold a little recently)
(Jennison and a bunch of other major institutional holders are not long-termers and have sold lots repeatedly and recently.)
1.15 million held by Powershares QQQ ETF (NASDAQ tracker, they have to add more as TSLA goes up)
1.20 million held by Baron Partners Retail and Focused Growth Retail (Ron Baron, "never sell" bull)
1.07 million held by Harbor Capital Appreciation Institutional (seems consistently bullish)
1.17 million held by Primecap (secretive, definitely long-termers, super low turnover; has sold some but might be cash outflows from mutual funds)
1.58 million held by BAMCO (seems consistently bullish after selling out in June 2013 and buying back in March 2014 -- *someone* isn't making the same mistake twice)
And some other big holders which are more likely to sell:
2.38 million held by Fidelity Blue Chip Growth (DOES sell sometimes)
1.88 million held by Fidelity Growth Company (DOES sell sometimes)
1.04 million held by Fidelity Advisor New Insights A
4.64 million held by other Fidelity funds
2.74 million held by T Rowe Price Growth Stock (usuallly bullish but did sell recently)
1.13 million held by T Rowe Price Blue Chip Growth (bought recently)
8.03 million held by various other T Rowe Price funds (many do sell)
1.36 million held by American Funds NVIT Growth II (managed by American Funds, a division of Capital Group)
1.33 million held by VA CollegeAmerica New Perspective 529E (managed by American Funds, a division of Capital Group)
2.07 million held by Capital World Investors (a different division of Capital Group -- they've been selling since 2012)
Anyway, I estimate 50.27 million shares in the hands of long-term "rarely sell" institutional investors / mutual funds. Plus whatever Tencent has accumulated above 5%. That leaves about 79.79 million shares floating (including the "fast trading" and "weak long" mutual funds and institutions). Minus whatever Tencent has accumulated.
There are 31.58 million shares short (as of the 13th, possibly more now). The shares sold short are bought by additional longs, so the "available for trading" shares are around 111.37 million, minus whatever Tencent has accumulated, and any "long-term longs" (like many of us) who I didn't get in my count. To cover the short shares, the short-sellers must buy 28% of this total. To put it another way, more than 28% of the shares currently available for trading were created by short sellers. They will have to buy them back and find enough "weak longs" to buy them back from. Every time there's good news this becomes harder.
If I guess that Tencent has grabbed another 4.9% (to stay just below the 10% reporting threshold), it would be another 8.08 milion shares off the market.
Addition to the S&P 500 would require a minimum of 4% of the "float" (according to certain definitions) be purchased by just the *biggest* S&P tracker funds. It'll probably be more like 10% (including "closest index" funds and funds which aren't allowed to invest in companies which haven't shown 4 quarters of profit). For this purpose, I'm not sure how they calculate "float", but I figure they basically just exclude Musk and Tencent, so 122.39 million. 4% is 4.89 million. 10% is 12.24 million.
This could bring us down to 59.47 million real shares which are really available for sale (not counting the possibility of a macro crisis causing massive index fund redemptions). With a short interest of 31.5 million... well, then the shorts have to buy one out of every three shares available for trading in order to close out their positions. A lot of buying pressure.
