Twenty-six stocks make up the six categories (and portfolios) in our model AI Semiconductor Stocks Portfolio. Here we're looking for the performances of each sub-portfolio and of each of its constituents for the week ending November 21st, and MTD.

The first 4 of the 6 sub-portfolios consists of those categories that account for the 4 specific steps in the manufacturing of semiconductors, namely:

1. the design of complex semiconductor chips using sophisticated electronic design automation (EDA) software, i.e. Our Model Pure-Play EDA Software Chip Design Stocks Portfolio;
2. the supply of equipment and material necessary to build and operate a semiconductor foundry, i.e., Our Model The Pure-Play Semiconductor Supplier Stocks Portfolio;
3. the foundries that fabricate the chips based on the designs provided by other semiconductor companies, i.e. Our Model Pure-Play Semiconductor Foundry Stocks Portfolio; and 
4. the companies that assemble chips into finished semiconductor components, test for defects, and provide the specialized packaging  necessary for shipping the chips around the world, i.e., Our Model Pure-Play Outsourced Semiconductor Assembly & Test Stocks Portfolio.

The other two categories are those major companies that:

1. design and sell hardware devices and semiconductor chips themselves while outsourcing their fabrication (i.e., are fabless) to a specialized manufacturer; i.e., Our Model Pure-Play Fabless Semiconductor Stocks Portfolio; and
2. those companies that do everything themselves in-house to control the entire production process from beginning to end i.e., Our  Model  Integrated Device Manufacturer Stocks Portfolio.

Our 6 Model AI Semiconductor Stocks Portfolio Categories

Overall, AI semiconductor stocks fell during the week ending November 21, 2025, due to valuation concerns, profit‑taking after Nvidia’s strong earnings, and broader “AI bubble” fears that triggered a sector‑wide correction. Specifically, the constituents changed prices this past week as identified below::

1. Our Model Pure-Play EDA Software Chip Design Stocks Portfolio: down 2.2% w/e November 21st; down 13.1% MTD
   • Constituents: 
     • Cadence Design Systems (CDNS) concentrates on system-level integration, packaging, and simulation-heavy workflows; and 
     • Synopsys (SNPS) is a full-stack chip design, IP licensing, and software security provider.
   • ​​​​​Price Change Catalyst(s):
     • SNPS fell 0.4% due to:
       • weakness in design IP revenue largely due to China export restrictions and foundry challenges;
       • Ansys integration expenses weighed on profitability; and
       • several firms, including Bank of America, cut ratings and targets after the q3 earnings miss, amplifying selling pressure.
     • CDNS fell 4.6% due to:
       • FY guidance regarding profit, revenue and EPS below Wall Street estimates, signaling slower growth ahead;
       • demand for design software in the automotive sector fell, reflecting broader industry headwinds.
       • Synopsys’ acquisition of Ansys raised concerns about Cadence losing share in multi-physics and simulation;
       • funds like Martin Currie trimmed stakes; and
       • insiders (including the CFO) sold shares, adding to downward momentum.
2. Our Model Pure-Play Semiconductor Supplier Stocks Portfolio: down 3.4% w/e November 21st; down 8.6% MTD
   • Constituents: provide essential equipment for manufacturing chips, such as lithography machines, etching, test, and packaging equipment, automation and inspection systems, and production materials such as chemicals, gases, wafers, and packaging.
     • Applied Materials (AMAT) is a major supplier of deposition; 
     • ASML Holding (ASML)  is a major supplier of lithography machines;
     • KLAC Corp. (KLAC) provides metrology; and 
     • Lam Research (LRCX) supplies etching equipment.
   • ​​​​​Price Change Catalyst(s): 
     • AMAT fell 0.9% due to:
       • warning from management that both sales and earnings would soften in the coming quarter despite stronger than expected Q4 results with higher demand only materializing in the second half of 2026, pushing out the growth timeline;
       • China’s share of revenue fell to 29%, down from a peak of 45% in early 2024, reflecting ongoing U.S. export restrictions and weaker demand; and
       • some analysts trimmed near‑term price target expectations, citing geopolitical risks and cyclical softness.
     • KLAC fell 3.3% due to:
       • investors continuing to take profits after a strong AI-driven rally in October of 12%; and
       • a stronger‑than‑expected U.S. jobs report that reduced odds of near‑term rate cuts, sparking a broad market reversal that hit tech stocks hardest
     • LRCX fell 3.8% due to:
       • investors continuing to take profits after a strong AI-driven rally in October of 17.6%; and
       • Morgan Stanley cutting Lam Research to Underweight from Equal-Weight, citing slowing growth in China and NAND memory after two strong years.
     • ASML fell 4.0% due to:
       • CEO Christophe Fouquet highlighting rising uncertainty from tariffs and global trade tensions, which clouded visibility on future demand; and
       • the trimming of its 2025 forecast and warning that growth may stall in 2026.
3. Our Model Pure-Play Semiconductor Foundry Stocks Portfolio: down 3.4% w/e November 21st; down 4.4% MTD 
   • Constituents: 
     • GlobalFoundries (GFS) and United Microelectronics (UMC) focus on fabricating mature nodes (12nm–90nm and 28nm-90nm, respectively); 
     • Taiwan Semiconductor (TSM) specializes in fabricating leading-edge (3nm, 5nm, 7nm) nodes as well as mature nodes; and
     • Tower Semiconductor (TSEM) focuses on analog, RF, power, and mixed-signal nodes for the automotive, industrial, and medical markets.
   • ​​​​​Price Change Catalyst(s):
     • GFS went up 2.8% due to:
       • it beating Q3 2025 earnings expectations, showing strength in automotive and communications infrastructure chips; 
       • it acquiring Singapore’s Advanced Micro Foundry, expanding its silicon photonics and AI infrastructure portfolio; and
       • Morgan Stanley and other firms expressing confidence in GFS’s long‑term growth prospects, despite near‑term volatility
     • UMC went up 1.4% due to:
       • it beating Q3 2025 earnings expectations;
       • it increasing fab utilization to 76%, signaling stronger demand recovery after a soft 2024;
       • growth in 22/28nm products drove sequential shipment increases, highlighting UMC’s niche strength; and
       • Wall Street Zen and others upgrading UMC to “Buy,” citing long‑term promise and financial strength.
     • TSM fell 3.4% due to:
       • China’s DeepSeek AI model introduction rattling investors, leading to a sharp selloff in TSM; and
       • Wall Street Zen cutting TSM from “strong buy” to “buy,” citing near‑term risks despite long‑term AI demand.
     • TSEM fell 5.8% due to:
       • it missed earnings expectations;
       • the locking in gains from rally earlier in November on strong RF infrastructure and silicon photonics growth; and
       • valuation concerns and slower growth in mobile RF.
4. Our Model Pure-Play Outsourced Semiconductor Assembly & Test Stocks Portfolio: down 0.9% w/e November 21st; down 5.0% MTD
   • Constituents: 
     • Amkor Technology (AMKR) is positioned as a U.S.-friendly OSAT partner, benefiting from reshoring and CHIPS Act incentives; and 
     • ASE Technology (ASX) is more diversified, with EMS capabilities and a stronger presence in consumer electronics and networking.
   • ​​​​​Price Change Catalyst: 
     • Amkor rose 1.2% due to:
       • positive sentiment swept after Nvidia announced a landmark $5 billion investment and strategic partnership with Intel, which investors saw as a bullish signal for chip packaging and testing companies like Amkor;
       • B. Riley raising its price target on Amkor, reinforcing bullish sentiment; and
       • Amkor hitting a new 52‑week high in early November, which attracted momentum traders and options flow.
     • ASE fell 5.4% due to:
       • valuation concerns with analysts flagging ASE’s near‑term downside risk, with forecasts suggesting potential retracement toward $11–12 from current $14;
       • October and November ATM segment revenues showed sequential declines, raising concerns about packaging/testing demand; and
       • Acadian Asset Management trimmed its position in ASE earlier in November, adding to downward pressure.
5. Our Model Integrated Device Manufacturer (IDM) Stocks Portfolio: down 5.7% w/e November 21st; down 6.1% MTD
   • Constituents: 
     • Analog Devices (ADI) reported a 25% YoY jump in revenue driven by EV battery management systems and industrial automation; 
     • Infineon Technologies (IFNNY); NXP (NXPI), and STMicroelectronics (STM) are key suppliers for ADAS, powertrain electrification, and vehicle connectivity, and EV penetration and silicon content per vehicle continues to rise, lifting analog and embedded chip demand.
     • Intel's (INTC) foundry push and AI accelerator roadmap are gaining traction; 
     • Microchip Technology (MCHP) and Texas Instruments  (TXN) saw renewed demand in factory automation, smart grid, and medical devices; and
     • Micron Technology (MU) benefited from rising demand for HBM and DDR5 memory in AI workloads,
   • ​​​​​Price Change Catalyst(s):
     • TXN had no change due to:
       • management guidance for Q4 revenue and EPS was below consensus, sparking concerns about near‑term growth;
       • industrial and automotive segments, which are core to TXN’s analog chip business,  showing signs of slowing demand, raising questions about cyclical exposure; and
       • asset managers like DNB and Bahl & Gaynor trimming positions in TXN during November, adding to downward pressure.
     • ADI fell 0.9% due to:
       • investors growing cautious ahead of its upcoming Q4 earnings release on November 25th (traders often trim positions before earnings when uncertainty is high).
     • NXPI fell 2.9% due to:
       • NXPI narrowly beating EPS expectations but reporting materially higher inventory levels, raising concerns about demand sustainability;
       • next‑quarter EPS guidance was only in line with consensus, which investors viewed as uninspiring; and
       • Kurt Sievers announcing plans to retire at year‑end, creating leadership uncertainty at a critical time.
     • Intel fell 2.9% due to:
       • Intel reporting razor-thin net margins of just 0.37% in its Q3 results raising concerns about profitability;
       • management providing weak EPS guidance for Q4, well below expectations, signaling near‑term earnings pressure; and
       • the consensus ratings leaning towards “Reduce,” with 23 Holds and 8 Sells, reflecting skepticism despite government incentives for domestic chipmaking.
     • MCHP fell 4.7% due to:
       • management reporting Q4 revenue and EPS below consensus (earlier in November), that continued to spark concerns about slowing demand; and
       • weakness in Industrial & automotive segments, which are core to MCHP’s analog and microcontroller business, showed signs of cyclical slowdown, echoing TXN’s cautious forecast;
     • STM fell 5.9% due to:
       • management conveying lower Q4 margins, citing rising costs and uneven demand;
       • softness in automotive and industrial demand; and 
       • sector‑wide analog chip weakness following Texas Instruments and Analog Devices’ cautious forecasts.
     • IFNNY fell 9.8% due to:
       • Analog peers TXN, ADI, NXPI, and STM all falling after weak guidance, pulling Infineon down in sympathy.
     • MU fell 16.0% on the week due to:
       • Micron’s CFO signaling increased capex ahead, raised concerns about profitability and free cash flow; and
       • traders locked in gains, amplifying downside momentum.
6. The Model Pure-Play Fabless Semiconductor Stocks Portfolio: down 6.5% w/e November 21st; down 13.0% MTD
   • Constituents: Advanced Micro Devices (AMD); Broadcom (AVGO); Marvell (MRVL); Monolithic Power (MPWR); Nvidia  (NVDA); and Qualcomm (QCOM). All six companies are deeply embedded in the AI hardware stack - from GPUs and NPUs to networking ASICs and power management ICs - and the increasing AI infrastructure demand, their strong executions, and their strategic positioning across cloud, edge, and automotive markets show continuing strength.
   • ​​​​​Price Change Catalyst(s): 
     • Broadcom fell 0.7% due to:
       • market commentary that flagged concerns that the AI boom may be peaking, leading to recalibration of growth expectations;
       • profit-taking after a surge of 14% since the end of August; and
       • near‑term caution around AI demand weighing on sentiment.
     • Monolithic Power fell 5.2% due to:
       • investors expecting Q3 revenue to be even higher than reported;
       • disappointment in management guidance of Q4 revenue which, while slightly ahead of consensus, investors viewed this as “not enough” given the stock’s premium valuation; and
       • traders locking in the 13% gain since the end of October, amplifying downside momentum.
     • Nvidia fell 5.9% due to:
       • market commentary flagging concerns that the AI boom may be peaking, leading to recalibration of growth expectations; and
       • profit-taking after a recent 12% surge in price.
     • Qualcomm fell 6.1% due to:
       • analysts flagging slowing Android handset shipments, especially in China, which directly impacts Qualcomm’s Snapdragon and modem revenues given U.S.–China trade tensions and tariff uncertainty which weighed on sentiment for handset‑exposed chipmakers;
       • Qualcomm’s prior earnings showed resilience in automotive and IoT, but management guided December‑quarter revenue only in line with consensus, disappointing investors who expected stronger upside;
       • profit-taking after a recent11% surge in price;
     • Marvell fell 10.4% due to: 
       • market chatter that suggested cloud providers may moderate AI server capex in 2026, pressuring sentiment for Marvell’s data‑center networking chips; and
       • profit-taking after a recent 21% surge in price.
     • AMD fell 17.4% due to:
       • .market chatter suggesting cloud providers may moderate AI server capex in 2026, pressuring sentiment for AMD’s MI300 accelerator line;
       • profit‑taking after a recent 25% rally; and
       • increasing concerns for rising costs for advanced packaging and fab partnerships raising questions about long‑term profitability.

Summary

The above 6 sub-portfolios in our model AI Semiconductor Stocks Portfolio fell an average of 4.5% w/e November 21st and 9.8% MTD. In comparison, the Nasdaq only fell 3.1% w/e November 21st and went down "only" 6.2% MTD. Several stocks that fell significantly last week were up on Friday and still have a chance to end the month in the green if Friday's trend holds.

More By This Author:

Pure-Play Quantum Computing Stocks Down 21% Last Week - Here's Why
Worst Day Ever For MSO Cannabis Stocks - Here's Why
What Are The Prospects For USA Rare Earth (USAR) And Its Warrant?