But you won't - you "own" an equal number of shares of TSLA indirectly through the index fund. If TSLA goes up, that part of your ETF has gone up. You're just b

But you won't - you "own" an equal number of shares of TSLA indirectly through the index fund. If TSLA goes up, that part of your ETF has gone up. You're just being simultaneously long and short the same stock. The only difference between that and "not owning TSLA" is that you're paying a bit to borrow the shares -- about 0.41% annually, right now.