SOXL vs SOXS

Why does SOXL go up when SOXS goes down?

SOXL is a 3x long semiconductor ETF: it aims to deliver three times the daily return of a semiconductor index. SOXS is the 3x inverse of the same index: it aims to deliver three times the opposite of that daily return. If the semis index is up 1% on the day, SOXL targets roughly +3% and SOXS targets roughly −3%. If the index falls 1%, the signs flip. They are two leveraged bets on the same underlying — one that the chip sector rises, one that it falls — and both reset their leverage every single day.

Same index, opposite leverage

Both funds track the same basket of large semiconductor companies, just with opposite signs and the same 3x multiplier. That symmetry is the whole point: a trader who is bullish on chips can express it through SOXL, and a trader who wants downside exposure can use SOXS without short-selling or options. Because the underlying is one of the most volatile corners of the equity market, the 3x layer makes both funds move violently in dollar terms — a routine day in the index becomes a large day in either ETF.

SOXX is the unleveraged iShares fund on the same ICE Semiconductor index the Direxion pair tracks. Invesco's SOXQ is often mentioned alongside it, but it follows a different index (the PHLX SOX), so it doesn't belong in a same-index column. Unleveraged means no reset decay — it does not mean it can't lose money.

Note the symmetry in that table is a target, not a promise. Tracking error, fees, and overnight gaps mean a ~10% index move is roughly a ~30% ETF move before those frictions, not exactly. The further you stray from a single day, the looser the 3x relationship gets.

Daily reset: why a ~10% index move is roughly a ~30% ETF move

The "3x" in both tickers describes one day. A leveraged ETF promises a multiple of the day's move, then rebalances overnight so it can promise the same multiple again tomorrow. Within a single session that math is clean: a ~10% move in the index implies roughly a ~30% move in the ETF, before gaps and slippage. The trouble starts the moment you hold across more than one day, because each day's reset compounds against the next.

This is exactly the mechanism that drives leveraged-ETF decay — and it hits SOXL and SOXS the same way, regardless of direction. A flat-but-choppy week can leave both the long and the inverse fund lower than where they started. The detailed compounding math, with a worked two-day example, lives in that companion piece; the takeaway for this page is simpler.

Multi-day decay and path dependence

Because leverage resets daily, your result depends not just on where the index ends up but on the path it took to get there. A smooth one-direction trend can let the compounding work in your favor and amplify a move; a violent, range-bound chop erodes value even if the index is net flat. This is called path dependence, and it is unavoidable in a daily-reset product.

The practical consequence: holding either SOXL or SOXS as a passive "set it and forget it" position is the misuse case that generates most of the horror stories. The issuers say as much in their own prospectuses — these are tactical, short-duration tools meant for traders who actively monitor and manage positions, not buy-and-hold investors.

Gap risk cuts both ways

Leverage magnifies every gap. If the semis index gaps 10% before you can react, a 3x ETF gaps roughly 30% — before any slippage. A protective stop is an instruction to sell once a price is touched; it does not guarantee that price, and in a gap the market can open well past your stop and fill you far lower. That risk applies to SOXL on a down-gap and to SOXS on an up-gap. With 3x leverage on a high-volatility sector, an ordinary overnight surprise can leave a much wider wound than the same news would on an unleveraged stock.

Why holding the inverse overnight is especially risky

SOXS deserves a sharper warning than its long sibling. Over the long run, equity indices have a structural upward drift, and the semiconductor sector in particular has trended higher across most multi-year windows. A 3x inverse fund fights that drift and pays the daily-reset decay tax, so SOXS tends to grind lower the longer it is held — even before a single bad gap. Combine that with the fact that bullish surprises (earnings beats, sector rallies) gap against the inverse fund, and overnight inverse exposure stacks two penalties at once: structural drift and gap risk. Neither penalty is a forecast about any particular night; both are properties of the product.

How a long-only rules engine uses the long — and why it never touches the inverse

This is the lens behind how Coil works — not a recommendation to trade these instruments, just an explanation of one disciplined approach to a hard pair. Coil is rules-based trading software you run yourself, on your own machine, broker, and capital. It scans the whole market — the S&P 500, the Nasdaq-100, and a Macro book (bonds, income, gold and metals, commodities) — scores every name for opportunity, entry-window, leadership and sector phase, and buys leaders at real entries. Leveraged vehicles like SOXL are exactly what it uses to accelerate a leader when the setup earns it — but only the long side, and only carefully:

• SOXL to accelerate a semis leader — at reduced size, at a real entry. When chips are a leading sector and the name (or the index) scores READY or SETUP — an oversold flush, a pullback to trend, a momentum reclaim — the engine can express that through the 3x long at reduced notional, precisely because the decay and gap math above make full-size leverage reckless. It never buys a FALLING name (a falling knife) and never CHASEs one pinned at its highs.
• It never shorts the inverse. Coil is long-only by design, so it does not touch SOXS at all. When the tape turns down it does not flip to the inverse — it raises cash and rotates defensively into the Macro book (bonds, gold, income). The structural upward drift and daily-reset decay that make SOXS so punishing to hold are exactly why a long-only engine sidesteps it rather than trying to time it — and when we tested the other side of that choice anyway, all 36 pre-registered hedges failed.
• Standing aside counts. When nothing scores a real entry, the engine holds cash rather than force a trade. Idle cash can earn the broker's own variable cash sweep (~3.35% APY on Robinhood Gold as of early 2026 — the broker's yield, variable, not paid by Coil, and not risk-free).

The discipline is validated, not asserted. In a point-in-time research backtest (2017–2026 H1, survivorship-free with delisted names included, next-open fills, costs modeled), the leadership-rotation backbone Coil's scoring is built on compounded +638% versus SPY's +282%, with a shallower worst drawdown (−23% vs −32%) and a positive result in 9 of 10 years (worst −1%, in 2018). Read the honest rider with it: through the end of 2025 it ran roughly even with SPY at about one-third less drawdown — the outperformance concentrates in leadership regimes (2025 +51%, 2026 H1 +86%). Those are research figures, not live results, and the engine is newly live. We publish that live record free and unauthenticated at /api/perf — engine versus SPY and QQQ since the engine's 2026-07-08 inception, funding-adjusted, percentages only, and omitted rather than estimated when the data will not support it. To put names to the jargon, the trading-bot glossary defines daily reset, decay, drawdown, and profit factor. If you want to weigh tooling approaches, see Coil vs. trading bots and signal services. None of this makes leveraged ETFs "safe."