Volatile trading persisted on the stock market last week as investors scrambled to react to a flurry of positive and negative news that sparked both buying and selling positions.

On Friday alone, all Wall Street main indices fell into the red territory, with trading dampened mainly by tariff threats and expectations of a higher inflation rate in the US.

Ten companies under mixed sectors also mirrored the decline, with each booking double-digit slumps. This article details which 10 companies suffered the most last week and what specifically caused investor pessimism.

To come up with last week’s worst performers, we considered only the stocks with at least $2 billion in market capitalization and $5 million in daily trading volume.

10. Illumina Inc. (NASDAQ:ILMN)

Illumina saw its share prices last week drop by 9.56 percent to $111.06 apiece from the $132.74 apiece on January 31, as investor sentiment was weighed down by an analyst’s downgraded rating for the company’s stock.

On Friday, TD Cowen cut its stock rating for ILMN to “hold” following poor earnings performance in the full year 2024.

In its earnings release, ILMN widened its net loss for the full year 2024 to $1.2 billion from the $1.16 billion registered in 2023 amid a 2.9-percent drop in revenues at $4.37 billion versus $4.5 billion year-on-year.

The company, however, achieved a net income of $187 million last quarter, a reversal from the $176 million net loss registered in the same period a year earlier.

According to TD Cowen, its downgraded outlook also considered weaker-than-expected next-generation sequencing consumable growth, increasing competition, and geopolitical risks in China.

9. Moderna Inc. (NASDAQ:MRNA)

Moderna Inc. dropped its share prices by 17 percent last week to finish at $32.6 from the $39.42 registered on January 31 as investor sentiment was dampened by false news reports that the pharmaceutical giant manufactured vaccines to fight COVID-19 two years before the pandemic emerged.

An online post claimed that MRNA had manufactured COVID-19 vaccines in 2017. The allegations, however, were immediately debunked by a report from Reuters, saying that data on mRNA vaccines sent by the pharmaceutical giant to European regulators during the period were for early tests of the mRNA platform to treat or prevent diseases such as cancer.

In other news, investors also repositioned their portfolios ahead of the final decision on Robert F. Kennedy Jr.’s nomination as the country’s next health secretary.

What feared investors in particular was Kennedy’s anti-vaccine stance, having been a prominent figure in the anti-vaccine movement over his doubts about vaccines’ safety and efficacy.

8. New Fortress Energy Inc. (NASDAQ:NFE)

Shares of New Fortress fell 15 percent last week to end Friday’s trading at $12.26 from January 31’s $15 finish as investors continued to sell off positions over twin news that it was being investigated by a shareholder law firm over revenue projection issues, while also earning a credit rating downgrade from an investment bank.

On Thursday, law firm Johnson Fistel LLP announced that it launched an investigation into NFE following a class action lawsuit over claims that it created the false impression of possessing reliable information on its projected revenue growth outlook, while simultaneously downplaying the risks associated with its Fast Liquefied Natural Gas projects.

The company also earned a pessimistic outlook from S&P Global Ratings on its credit rating, as it downgraded NFE from “B+” to “B” due to concerns about its liquidity and high leverage.

S&P said the downgrade also reflected its outlook on the company’s financial health.

7. Semtech Corp. (NASDAQ:SMTC)

Semtech shares retreated by 18.6 percent last week from the $66.96 finish on January 31 to end Friday’s trading at $54.51 apiece following a stock rating downgrade from an analyst, citing slower take-up in the chipmaker’s products.

Shares of the company were trading around the $60 level most of the week before losing momentum after Baird analysts markedly lowered their price target for SMTC to $60 from $80 previously while maintaining an “outperform” rating on the stock.

The analysts cited slower-than-expected take-up in SMTC’s active copper cables (ACC), which offer extended reach to allow for high-volume switch-to-server connections.

The brokerage firm also noted that it observed muted activity in overall ACC take-up.

“ACC benchmarking activity has been muted in the past few months outside of Meta. ACCs and LPOs remain a medium-term opportunity for Semtech and are the basis for our Outperform rating; however, investors should brace for near-term turbulence,” Baird said in its note.

6. Neurocrine Biosciences Inc. (NASDAQ:NBIX)

Shares of Neurocrine plummeted 19 percent week-on-week to close Friday’s trading at $122.62 each as investors digested its lackluster fourth-quarter earnings performance and conservative outlook guidance for 2025.

In its earnings release last week, NBIX said net income in the last quarter fell by 30 percent to $103.1 million from the $147.7 million reported in the same period last year, despite revenues increasing by 21.8 percent to $627.7 million from $515.2 million.

Revenues for the full year increased by 24.8 percent to $2.355 billion from $1.887 billion, pushing net income higher by 36.68 percent at $341.3 million versus the $249.7 million registered in 2023.

For this year, NBIX merely reported a conservative outlook, saying full-year net product sales are projected to settle between $2.5 billion and $2.6 billion.

“With a rapidly advancing and growing pipeline and a strong financial profile, we are well positioned to build a leading neuroscience company,” said NBIX CEO Kyle Gano.

5. Skyworks Solutions Inc. (NASDAQ:SWKS)

Skyworks saw its share prices drop by 26 percent last week to close at $65.69 apiece from the $88.76 registered a week earlier as investors sold off positions following an announcement that technology giant Apple Inc. it would reduce its reliance on Skyworks’ semiconductors for components of its upcoming iPhone 17.

This spells bad news for the company, with Apple being one of its largest customers. Last quarter alone, Apple accounted for 72 percent of SWKS’ total revenues.

According to SWKS’ Chief Finance Officer Kris Sennesael, the company’s content share in the new iPhone is expected to decline by up to 25 percent despite securing multiple sockets, including highly integrated RF modules.

Following the announcement, a number of investment banking firms moved to downgrade Skyworks’ rating.

Analysts from Stifel said they slashed their stock rating for the company from “buy” to “hold,” while Mizuho analysts said they cut their rating for the company from “outperform” to “neutral,” citing continued headwinds through at least the iPhone 18 launch and limited near-term catalysts.

4. Newell Brands Inc. (NASDAQ:NWL)

Shares of Newell Brands declined by 28.4 percent last week to end Friday’s trading at $7.13 each versus the $9.96 registered on January 31 as the company’s dismal earnings performance last year weighed down on the company’s shares.

In the last quarter of 2024, NWL reported 8.4 percent lower net sales at $1.9 billion versus the $2.076 billion registered in the same period last year. Meanwhile, net sales for the full year 2024 declined to $7.5 billion from $8.13 billion in 2023.

Despite the revenue drop, NWL was able to narrow its net loss by 37 percent to $54 million from $86 million during the quarter as well as by 44.3 percent at $216 million from $388 million for the full year.

For this year, NWL said it expects even lower, with figures declining between 2 to 4 percent.

NWL is one of the leading consumer goods companies that owns brands such as Rubbermaid, Sharpie, Graco, Coleman, Rubbermaid Commercial Products, Yankee Candle, Paper Mate, FoodSaver, Dymo, EXPO, Elmer’s, Oster, NUK, Spontex and Campingaz.

3. elf Beauty Inc. (NYSE:ELF)

Shares of elf Beauty declined by 28.9 percent last week to close at $71.13 each versus the $99.91 registered on January 31, mainly due to a lower earnings outlook for fiscal year 2025.

In its latest earnings release, ELF lowered its full-year 2025 sales outlook to between $1.3 billion and $1.31 billion from $1.31 billion to $1.33 billion previously.

“Given softer-than-expected trends in January, we are taking a prudent approach and lowering our outlook for the final quarter of our fiscal year. Our updated outlook for fiscal 2025 reflects an expected 27-28 percent year-over-year increase in net sales, as compared to an expected 28-30 percent increase previously,” said ELF Chief Finance Officer Mandy Fields.

In the third quarter of fiscal year 2025, ELF saw net income drop by 35.8 percent to $17.26 million from $26.89 million, while net income for the first nine months fell by 26 percent to $83.8 million from $113 million year-on-year.

2. Bill Holdings Inc. (NYSE:BILL)

Bill Holdings nosedived by 35.8 percent week-on-week to close at $62.13 last Friday from the $96.77 registered on January 31 as investors appeared to have snubbed its strong earnings performance last year amid lower-than-expected revenue guidance for the third quarter of fiscal year 2025.

In its latest earnings call, BILL said it projects revenues in the third quarter to settle between $352.5 million to $357.5 million, way below the $360.4 million analysts projected.

For the full year, BILL expects revenues to end between $1.45 billion and $1.47 billion.

In the last quarter, BILL swung to a net income of $33.55 million, reversing a $40.4 million net loss. It also achieved a net income of $42.46 million in six months ending December, reversing a net loss of $68.28 million.

BILL is a company providing financial operations platforms for small and midsize businesses (SMBs).

1. FMC Corp. (NYSE:FMC)

Shares of FMC Corp. fell by 38 percent week-on-week, ending Friday’s trading at $34.54 each from the $55.78 registered on January 31, as investors were disappointed by a plunge in its earnings performance in the fourth quarter and full year of 2024.

In a statement last week, FMC Corp. said net profit for the full year 2024 plummeted by 74 percent to $342 million while revenues declined by 5 percent to $4.25 billion.

In the fourth quarter alone, the company swung to a net loss of $16 million, reversing a net income in the same quarter in 2023.

Revenues for the quarter, however, increased by 7 percent to $1.22 billion.

For the full year 2025, the company also posted a conservative outlook, with revenues expected to settle between $4.15 billion and $4.35 billion, flat from 2024.

Following the release, UBS downgraded its rating for the company to “neutral” from “buy” given ongoing pressure from declining crop chemical demand.

It also slashed its price target by 42 percent to $38 apiece from $66 previously.

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