In its 13F for Q1 2026 (holdings as of March 31, 2026, filed May 15, 2026), Harvey Partners, LLC reported 45 stock positions worth $1.2 billion . Its top holding was Adeia (ADEA) at 5.4% of the portfolio, followed by Enpro (NPO, 5.2% ) and MKS (MKSI, 4.5% ). Compared with Q4 2025, it opened 6 new positions, sold out of 4, added to 25 and reduced 14. The biggest buy was a new position in Pool (POOL) and the biggest sale Great Lakes Dredge & Dock (GLDD, shares −84% ).
Location Tarrytown, NY
CIK 0001406484
Portfolio Value $1.2B (Q1 2026) Holdings 45 stocks · $1.2B Holdings quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock % Of Portfolio ▼ Shares Held Total Value Change vs Q4 2025 ADEA Adeia Inc. 2,754,500 $66.2M Add +5.3% NPO Enpro Inc. 253,500 $63.5M Add +1.7% MKSI MKS Inc. 243,396 $55.9M Reduce -15.8% NGVT Ingevity Corp. 743,500 $53.0M Add +18.1% BWXT BWX Technologies Inc. 255,300 $52.2M Add +1.5% AZZ Azz Inc. 351,500 $44.0M Reduce -3.6% MTRN Materion Corp. 293,121 $42.4M Reduce -8.3% WCN Waste Connections Inc. 258,500 $42.0M Add +15.3% LFUS Littelfuse Inc. 121,500 $41.2M Add +3.4% NOVT Novanta Inc. 320,000 $37.8M Add +5.3% MLM Martin Marietta Materials 63,925 $37.6M Add +25.0% ASTE Astec Industries Inc. 672,200 $36.2M Add +8.1% BV Brightview Holdings Inc. 2,938,000 $34.6M Add +12.6% BATRK Atlanta Braves Holdings in-C 806,000 $34.4M Add +8.6% THRM Gentherm Inc. 1,233,500 $34.3M Add +17.9% BALL Ball Corp. 560,000 $33.1M Add +23.8% THR Thermon Group Holdings Inc. 646,728 $32.6M Reduce -16.2% AWI Armstrong World Industries 196,000 $32.3M Add +14.3% RTO Rentokil Initial PLC-SP ADR 975,500 $30.7M Add +10.1% ULS Ul Solutions Inc. Class A 342,500 $29.4M Add +11.3% CTS CTS Corp. 594,400 $28.4M Add +9.3% CALX Calix Inc. 572,500 $28.0M Add +7.3% POOL Pool Corp. 135,000 $27.3M New SMG Scotts Miracle-Gro Co. 437,500 $26.6M Add +98.9% NOK Nokia Corp.-Spon ADR 2,945,500 $23.7M Reduce -11.8% LASR Nlight Inc. 413,584 $23.6M Reduce -65.6% CWST Casella Waste Systems Inc. Class A 281,500 $22.3M Add +43.5% ICHR Ichor Holdings Ltd. 469,179 $21.9M Reduce -2.8% MANU Manchester United PLC Class A 1,212,500 $20.4M Add +9.9% BCPC Balchem Corp. 114,800 $19.5M Reduce -1.0% VPG Vishay Precision Group 401,571 $17.4M Add +5.2% KN Knowles Corp. 664,500 $17.1M Add +1.8% CHKP Check Point Software Tech 109,500 $15.6M Reduce -11.1% PANW Palo Alto Networks Inc. 91,000 $14.6M New RSKD Riskified Ltd. Class A 3,396,000 $13.3M Add +9.7% FWONK Liberty Media Corp. Class C 123,500 $10.5M New MTRX Matrix Service Co. 905,000 $10.4M Add +6.1% GLDD Great Lakes Dredge & Dock Co. 610,000 $10.4M Reduce -83.5% WH Wyndham Hotels & Resorts Inc. 121,000 $9.8M New DNOW Dnow Inc. 730,943 $8.7M Reduce -62.3% OEC Orion SA 1,304,000 $8.5M Reduce -45.9% SPY SS SPDR S&P 500 ETF Trust-US 13,000 $8.5M New FWONA Liberty Media Corp. Class A 60,000 $4.7M New APLD Applied Digital Corp. 150,000 $3.6M Reduce -40.0% VRNS Varonis Systems Inc. 140,000 $3.0M Reduce -65.5%
Options reported separately and not counted above: QQQ puts ($17.3M), IWM puts ($8.1M).
Portfolio Sells Q4 2025 → Q1 2026 Portfolio Sells quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock Change vs Q4 2025 % Of Portfolio Change To Portfolio ▲ GLDD Great Lakes Dredge & Dock Co. Reduce -83.5% 0.84% −3.52 LASR Nlight Inc. Reduce -65.6% 1.92% −2.13 CYBR Cyberark Software Ltd./Israel Sold out 0.00% −1.77 DNOW Dnow Inc. Reduce -62.3% 0.71% −1.60 VRNS Varonis Systems Inc. Reduce -65.5% 0.24% −0.95 VOO Vanguard S&P 500 ETF Sold out 0.00% −0.80 CHKP Check Point Software Tech Reduce -11.1% 1.27% −0.78 OEC Orion SA Reduce -45.9% 0.69% −0.45 APLD Applied Digital Corp. Reduce -40.0% 0.29% −0.26 MIAX Miami International Holdings Sold out 0.00% −0.20 MTRN Materion Corp. Reduce -8.3% 3.44% −0.12 NP Neptune Insurance Holdi Class A Sold out 0.00% −0.05 BCPC Balchem Corp. Reduce -1.0% 1.58% −0.02 NOK Nokia Corp.-Spon ADR Reduce -11.8% 1.92% −0.02 AZZ Azz Inc. Reduce -3.6% 3.57% +0.06 THR Thermon Group Holdings Inc. Reduce -16.2% 2.65% +0.07 MKSI MKS Inc. Reduce -15.8% 4.54% +0.39 ICHR Ichor Holdings Ltd. Reduce -2.8% 1.78% +0.98
Portfolio Buys Q4 2025 → Q1 2026 Portfolio Buys quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock Change vs Q4 2025 % Of Portfolio Change To Portfolio ▼ POOL Pool Corp. New 2.22% +2.22 ADEA Adeia Inc. Add +5.3% 5.38% +1.32 PANW Palo Alto Networks Inc. New 1.19% +1.19 SMG Scotts Miracle-Gro Co. Add +98.9% 2.16% +1.01 NGVT Ingevity Corp. Add +18.1% 4.30% +0.96 FWONK Liberty Media Corp. Class C New 0.85% +0.85 WH Wyndham Hotels & Resorts Inc. New 0.80% +0.80 SPY SS SPDR S&P 500 ETF Trust-US New 0.69% +0.69 LFUS Littelfuse Inc. Add +3.4% 3.35% +0.68 BALL Ball Corp. Add +23.8% 2.69% +0.54 ASTE Astec Industries Inc. Add +8.1% 2.94% +0.52 FWONA Liberty Media Corp. Class A New 0.38% +0.38 NPO Enpro Inc. Add +1.7% 5.16% +0.37 BWXT BWX Technologies Inc. Add +1.5% 4.24% +0.34 CTS CTS Corp. Add +9.3% 2.31% +0.21 ULS Ul Solutions Inc. Class A Add +11.3% 2.38% +0.21 MLM Martin Marietta Materials Add +25.0% 3.06% +0.20 BATRK Atlanta Braves Holdings in-C Add +8.6% 2.80% +0.17 RTO Rentokil Initial PLC-SP ADR Add +10.1% 2.49% +0.15 KN Knowles Corp. Add +1.8% 1.39% +0.13 VPG Vishay Precision Group Add +5.2% 1.42% +0.10 CWST Casella Waste Systems Inc. Class A Add +43.5% 1.81% +0.09 MANU Manchester United PLC Class A Add +9.9% 1.66% +0.08 MTRX Matrix Service Co. Add +6.1% 0.84% −0.05 WCN Waste Connections Inc. Add +15.3% 3.41% −0.12 BV Brightview Holdings Inc. Add +12.6% 2.81% −0.15 NOVT Novanta Inc. Add +5.3% 3.07% −0.18 CALX Calix Inc. Add +7.3% 2.28% −0.26 RSKD Riskified Ltd. Class A Add +9.7% 1.08% −0.30 AWI Armstrong World Industries Add +14.3% 2.62% −0.32 THRM Gentherm Inc. Add +17.9% 2.78% −0.63
Options Activity Q4 2025 → Q1 2026 Security Type Change vs Q4 2025 Underlying Shares Value ▼ QQQ Invesco QQQ Trust Series 1 put New 30,000 $17.3M IWM iShares Russell 2000 ETF put Reduce -45.8% 32,500 $8.1M
Calls and puts are listed by the shares they cover; their value is not part of the stock holdings above.
All Filings Quarter Positions 13F Reported Value Top Holdings Q2 2026 47 $1.4B NPO, MTRN, MKSI, NGVT, ADEA Q1 2026 45 $1.2B ADEA, NPO, MKSI, NGVT, BWXT Q4 2025 43 $1.1B NPO, GLDD, MKSI, ADEA, LASR Q3 2025 44 $1.1B NPO, BWXT, AZZ, GLDD, ADEA Q2 2025 41 $1.0B AZZ, WCN, BWXT, BV, NPO Q1 2025 41 $843.4M WCN, AZZ, ADEA, RTO, NPO Q4 2024 41 $887.1M AZZ, WCN, ADEA, GLDD, RTO Q3 2024 42 $869.5M AZZ, WCN, BWXT, GLDD, ADEA Q2 2024 39 $808.6M AZZ, WCN, BWXT, HII, OEC Q1 2024 40 $921.9M AZZ, BWXT, HII, VRNS, OEC