Monday, August 10, 2026 was a quiet day at the index level — the S&P 500 building modestly on last week’s gains — but that calm surface masked some genuinely brutal single-stock action underneath. Two clinical-stage biotechs lost more than 85% of their value apiece on failed trial data within hours of each other. A data-analytics company got legally forced into completing an acquisition it had tried to walk away from. And a scattering of earnings and guidance disappointments hit names well outside the mega-cap spotlight. Here are 10 top stock losers today.
Top Loser Stocks Today — August 10, 2026:
1. TENX — Tenax Therapeutics, Inc. | $1.69 | −87% | Market Cap: ~$59M
Full Data Snapshot:
| Metric | Value |
|---|---|
| Closing Price | $1.69 |
| Session Loss | −87% |
| Previous Close | $13.45 |
| Day’s Range | $1.43–$1.79 |
| 52-Week High | $19.19–$19.40 |
| 52-Week Low | $1.43 |
| Market Cap | ~$59.02 million |
Tenax Therapeutics collapsed after the clinical-stage cardiopulmonary drugmaker announced its experimental drug TNX-103 (levosimendan) did not meet statistical significance on the primary endpoint of improvement in six-minute walk distance versus placebo. The stock gapped down dramatically in premarket trading, falling from the $12 range to near $2 before stabilizing in a tight band for the rest of the session. Tenax carries roughly $118 million in cash with no debt, giving it a sizable operating runway despite the setback, but shares are now down 74.71% year-over-year and nearly 88% over the past six months, wiping out virtually all of the gains built up earlier in 2026.
2. SION — Sionna Therapeutics, Inc. | $4.10 | ~−90% | Market Cap: Sharply Reduced
Full Data Snapshot:
| Metric | Value |
|---|---|
| Closing Price | $4.10 |
| Previous Close | $51.04 |
| Day’s Range | $4.01–$5.00 |
| 52-Week High | $54.97 (set August 7, 2026) |
| 52-Week Low | $4.01 |
| Average 12-Month Price Target (pre-collapse) | $53.20 |
Sionna Therapeutics suffered one of the single worst one-day collapses of the year after disclosing that its experimental cystic fibrosis drug SION-719 failed to improve sweat chloride levels — a key measure of CFTR protein function — in a mid-stage study. The company confirmed it will not advance SION-719 as an add-on treatment to Vertex Pharmaceuticals’ standard therapy Trikafta after the drug missed the study’s main activity goal. The irony is stark: Sionna had closed at an all-time high of $51.04 just one trading session earlier, on August 7, and Vertex Pharmaceuticals (VRTX) itself rose roughly 6.6–8% today partly because Sionna’s failure removed a perceived competitive threat to Trikafta’s franchise.
3. AIOT — PowerFleet, Inc. | −27% | Market Cap: Small-Cap SaaS
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −27% |
| Q2 Revenue | $110.8 million |
| Revenue Estimate | $115.7 million |
| Adjusted EBITDA | $21.5 million |
| Adjusted EBITDA Estimate | $25.6 million |
| FY27 Revenue Guidance (cut) | $468M–$473M, down from $485M–$490M |
| FY27 Adj. EBITDA Guidance (cut) | $111M–$114M, down from $122M–$125M |
PowerFleet, a small-cap AI-of-things (AIoT) SaaS provider serving fleet management and logistics customers, posted Q2 revenue growth of 6.4% year-over-year, but the growth rate and the dollar figures both missed Wall Street’s expectations, and adjusted EBITDA came in well below consensus as well. Management’s decision to cut full-year fiscal 2027 guidance on both revenue and EBITDA compounded the disappointment, particularly after the stock had carried a “Top Pick for 2026” designation from at least one analyst earlier in the year. This is a name that had also flagged a South African National Treasury contract worth $100–$120 million in prior updates — underscoring how much today’s move was about the guidance cut specifically rather than a loss of underlying business momentum.
4. MNDY — Monday.com Ltd | −10% | Market Cap: Mid-Cap SaaS
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −10% |
| Q2 EPS | $1.48 |
| EPS Estimate | $1.11 |
| Q2 Revenue | $364.6 million |
| Revenue Estimate | $355.53 million |
| Q3 Revenue Guidance | $368M–$370M |
| Q3 Revenue Estimate | $372 million |
| FY26 Revenue Guidance (reaffirmed) | $1.466B–$1.474B |
Monday.com’s decline is a case study in “beat the quarter, miss the guide.” The Work OS platform actually topped both EPS and revenue estimates comfortably for the quarter just reported, but third-quarter revenue guidance of $368–$370 million came in below the $372 million analysts were modeling, and that forward-looking miss overwhelmed the backward-looking beat. The stock’s full-year guidance was reaffirmed rather than raised, reinforcing the market’s read that growth is decelerating even as current-quarter execution remains solid.
5. COHR — Coherent Corp | −11.6% | Ahead of Scheduled Earnings
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −11.6% |
| Scheduled Earnings Date | August 12, 2026 |
Coherent, the laser and photonic-component maker that supplies transceivers into AI datacenter networking infrastructure, fell sharply today even without a specific news catalyst, ahead of its scheduled August 12 earnings report. The move reads as profit-taking following one of the stock’s most aggressive short-term rallies of the year, with investors locking in gains before the print rather than reacting to any new disclosure.
6. FSLR — First Solar, Inc. | −5.6% | Profit-Taking After Tariff Rally
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −5.6% |
First Solar declined today amid profit-taking and renewed concern about policy support, following what had been a roughly 14% tariff-fueled rally in the solar name over recent sessions. As with Coherent, there was no fresh negative catalyst specific to First Solar today — the pullback reflects investors trimming exposure after an outsized short-term run.
7. VRSK — Verisk Analytics, Inc. | −6.5% | Forced Into a Deal It Tried to Kill
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | More than −6.5% |
| Forced Deal Value | $2.35 billion |
| Target | AccuLynx |
Verisk Analytics fell after a Delaware judge ruled Friday that the data-analytics company must proceed with its previously terminated $2.35 billion acquisition of AccuLynx. Verisk had walked away from the deal in December, citing the fact that a Federal Trade Commission review of the merger wasn’t completed by the transaction’s termination date — but the court’s ruling forces the company back into the transaction, an outcome the market is reading as a loss of deal-optionality and a signal of unwanted capital commitment.
8. B — Barrick Mining Corporation | ~−5–6% | Q2 Earnings Miss Despite Strong Production
Full Data Snapshot:
| Metric | Actual | Estimate |
|---|---|---|
| Adjusted EPS | $0.82 | $0.84–$0.94 (sources vary) |
| Revenue | $5.29 billion | $4.53B–$5.67B (sources vary) |
| Gold Production | 796,000 oz (beat guidance of 730,000–770,000 oz) | — |
| Gold Cost of Sales | $1,993/oz | vs. $1,654/oz year-ago |
Barrick Mining fell despite reporting a $1.95 billion settlement agreement with Newmont that resolves a longstanding Nevada joint-venture dispute and clears the way for a planned IPO of Barrick’s North American gold assets by year-end. The stock declined anyway because adjusted earnings and revenue both missed Wall Street’s expectations, driven by rising production costs — gold cost of sales jumped to $1,993 per ounce from $1,654 a year earlier, reflecting lower processed grades and higher fuel and royalty expenses. Barrick also declared a $0.175 per share quarterly dividend and repurchased $1.2 billion of stock during the quarter. Some analysts characterized today’s decline as partly a healthy pullback after the stock had rallied nearly 30% since mid-July and remains up 78% over the past twelve months.
9. EBAY — eBay Inc | −4% | A Potential Suitor Gets Cold Feet
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −4% |
| Reported Bid Under Reconsideration | $56 billion |
eBay fell after Bloomberg reported that GameStop CEO Ryan Cohen is considering withdrawing the company’s roughly $56 billion bid for eBay, citing people familiar with the matter. A withdrawn or reconsidered acquisition bid removes a takeover premium that had been supporting the stock, contributing directly to today’s decline.
10. INTC — Intel Corporation | −3% | A Large Capital Raise Signals Dilution
Full Data Snapshot:
| Metric | Value |
|---|---|
| Session Loss | −3% |
| Public Offering Size | $15 billion |
| Underwriter Over-Allotment Option | Up to $2.25 billion additional |
Intel shares slipped after the company announced a $15 billion underwritten public offering of common stock, with underwriters granted a 30-day option to purchase up to an additional $2.25 billion in shares at the public offering price. Large share issuances like this typically weigh on a stock in the near term because they dilute existing shareholders’ ownership stake, even when the capital raised is intended to fund strategic priorities like foundry expansion.
Other Notable Weakness Today
A handful of additional names also traded lower without cracking the top 10 by percentage move: SK Hynix (SKHY) slid amid broad, sentiment-driven chip-sector weakness tied to renewed geopolitical tensions around U.S. strikes on Iran, with the American depositary shares tracking a sharper decline in Seoul trading overnight. Apple also declined roughly 1% after Jefferies downgraded the stock to Underperform from Hold.
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Disclaimer: This publication is entirely for informational and journalistic purposes and does not constitute formal financial, investment, or legal advice. All market investments carry inherent risks of capital loss. Always complete independent due diligence prior to executing equity trades.
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