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SOXL vs SOXS: the inverse pair, and why both decay

The inverse of SOXL is SOXS. Here's how the 3x long and 3x inverse semiconductor ETFs actually work, why they decay, and how a disciplined long-only engine treats each.

Learn · 6 min read · updated July 2026

Quick answer: the inverse of SOXL is SOXS. SOXL itself is not an inverse ETF. SOXL is the Direxion Daily Semiconductor Bull 3X ETF (targets 3× the index's daily return); SOXS is the Bear 3X fund on the same index (targets 3× the opposite of that daily return). Both reset daily — so over multi-day holds neither cleanly mirrors the other, and both can lose money in choppy tape. Details below.

The pair at a glance

FactSOXLSOXS
IssuerDirexion
LaunchedMarch 2010 — both funds, same day
Daily objective+3× the index's daily move−3× the index's daily move
Index trackedThe same U.S. semiconductor index — which is why their daily moves mirror by design
Daily correlation−1 by construction (daily only; multi-day paths diverge via reset decay)
Leverage resetDaily — neither fund tracks 3× over any period longer than one session

Structural facts only — expense ratios and assets change; check Direxion's fund pages for current figures.

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.

Read this first. SOXL and SOXS are 3x leveraged ETFs engineered for very short holding periods. They can lose value rapidly — including the total loss of the position — and the inverse fund is especially dangerous to hold overnight. Nothing on this page is investment advice, a recommendation, or a forecast. You own the keys, the capital, and the risk.

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.

Why Coil wrote this. Coil is long-only rules software you run yourself — it scores every name in the S&P 500, the Nasdaq-100 and a Macro book, and uses long leveraged vehicles like SOXL only to accelerate a leader at reduced size. It never trades SOXS. The pair's mechanics are a constraint we design around, which is why we wrote them out. Either tape is manageable by rule: in a bull market, if semis lead, Coil swings the leader — SOXL as the accelerant; in a free fall it doesn't flip to the inverse, it shortens its horizon to intraday and rotates defensive. Either way the vehicle has to prove it's ready — score a real entry — before anything is bought.

AttributeSOXLSOXSSOXX (1x)
Direction3x long (bullish)3x inverse (bearish)1x long (unleveraged)
Daily target vs. index+3× the index's daily move−3× the index's daily move~ the index itself
Index up 1% on the day~ +3%~ −3%~ +1%
Index down 1% on the day~ −3%~ +3%~ −1%
Leverage resetDailyDailyNone
Decay in choppy marketsYesYesNo leverage-reset decay
Designed holding periodIntraday to a few daysIntraday — overnight especially riskyAny horizon an index fund suits

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.

"Actively monitor and manage" is the issuers' own phrase, and it is doing a lot of work — almost nobody watches a 3x fund every few minutes for a week straight. Coil Live (MCP feed) sells that watching for $29 a month: the scored board with a structural stop and target on each name, re-scored about every 5 minutes through the market day, read by your own AI agent over MCP or plain HTTPS. The engine behind it is long-only, so nothing it serves will ever hand your agent a reason to buy SOXS. Your agent places the orders at your own broker, and Coil never sees the account.

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.

Neither fund "goes to zero" on a normal day — issuers use reverse splits to keep the share price off the floor and exchange circuit breakers halt extreme single-day moves. But a single catastrophic session can wipe out most of a 3x position, and prolonged decay can trend either fund toward worthlessness over long holds. Treat total loss of the position as a real, live possibility, not a tail you can ignore.

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."

Educational only. Nothing here is a buy or sell recommendation, financial advice, or a forecast. SOXL and SOXS carry substantial risk including total loss. Decide for yourself, or talk to a licensed adviser.

FAQ

What is the inverse of SOXL?

The inverse of SOXL is SOXS. SOXL is the Direxion 3x long semiconductor ETF (it targets three times the daily return of a semiconductor index); SOXS is the 3x inverse fund on the same index (it targets three times the opposite of that daily return). Both reset daily, so neither tracks its multiple over multi-day holds.

Is SOXS the exact opposite of SOXL?

Only on a single day. Both funds reset their 3x exposure daily, so over multi-day holds compounding and volatility decay pull each fund away from a clean mirror of the other — in choppy tape both SOXL and SOXS can lose money over the same stretch.

Is it safe to hold SOXS overnight?

Holding a 3x inverse ETF overnight carries outsized gap risk: a positive overnight move in semiconductors lands as roughly three times that against SOXS at the open, before any stop can act. Inverse leveraged funds are engineered for very short holding periods, and both funds can lose value rapidly, including the total loss of the position. This is general information, not investment advice.

Is SOXL an inverse ETF?

No. SOXL is the Direxion Daily Semiconductor Bull 3X ETF — it targets three times the semiconductor index's daily return in the same direction. The inverse fund is SOXS (Bear 3X), which targets three times the opposite of that daily return. Confusing the two inverts the direction of the trade.

What is the unleveraged version of SOXL and SOXS?

SOXX — the iShares fund on the same ICE Semiconductor index the Direxion pair tracks, with no daily leverage reset and therefore no reset decay. Invesco's SOXQ is often mentioned alongside it but follows a different index (the PHLX SOX). Unleveraged does not mean it cannot lose money.

Leverage used with discipline, not abandon

Coil is software you run yourself — a long-only leader engine that accelerates with leveraged vehicles at reduced size, times entries (READY/SETUP, never chasing or catching a falling knife), and rotates to cash and Macro instead of shorting. Read how it works.

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Want to see the rules drive these vehicles first? How an AI agent automates SOXL/SOXS by rule.

Coil is software you install and run yourself, with your own brokerage credentials and capital. It is long-only and not investment advice, not a managed account, and not a signal service. Leveraged ETFs, where the engine uses them, can lose value rapidly, including total loss. All performance figures are research backtests — point-in-time and survivorship-free, not live or client returns; past performance does not predict future results.