Ranked by reported Q2 2026 13F market value
Share of total reported institutional value in ACLS held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 5.0M | $952.8M | +1.9% | 16.364% | 0.01% |
| 2 | FMR LLC | 4.1M | $781.7M | +69.7% | 13.425% | 0.03% |
| 3 | VANGUARD PORTFOLIO MANAGEMENT LLC | 2.5M | $469.6M | -0.4% | 8.066% | 0.02% |
| 4 | VANGUARD CAPITAL MANAGEMENT LLC | 1.4M | $262.7M | +0.3% | 4.511% | 0.01% |
| 5 | STATE STREET CORP | 1.2M | $233.2M | +3.5% | 4.006% | 0.00% |
| 6 | VICTORY CAPITAL MANAGEMENT INC | 1.1M | $214.8M | -11.3% | 3.690% | 0.12% |
| 7 | REINHART PARTNERS, LLC. | 929K | $175.9M | -44.0% | 3.022% | 4.02% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 834K | $158.0M | +2.8% | 2.712% | 0.01% |
| 9 | BNP Paribas Asset Management Holding S.A. | 803K | $152.2M | -20.2% | 2.613% | 0.15% |
| 10 | DIMENSIONAL FUND ADVISORS LP | 709K | $134.3M | -16.0% | 2.308% | 0.02% |
| 11 | BALYASNY ASSET MANAGEMENT L.P. | 616K | $116.7M | -54.8% | 2.005% | 0.15% |
| 12 | PRIMECAP MANAGEMENT CO/CA/ | 610K | $115.6M | -7.3% | 1.986% | 0.07% |
| 13 | Invesco Ltd. | 528K | $100.0M | +219.7% | 1.717% | 0.01% |
| 14 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 416K | $78.9M | -6.6% | 1.354% | 0.01% |
| 15 | BARROW HANLEY MEWHINNEY & STRAUSS LLC | 392K | $74.3M | +688040.4% | 1.276% | 0.23% |
| 16 | JANE STREET GROUP, LLC | 389K | $73.7M | +1104.3% | 1.266% | 0.01% |
| 17 | MANUFACTURERS LIFE INSURANCE COMPANY, THE | 384K | $72.7M | -22.0% | 1.249% | 0.03% |
| 18 | NORTHERN TRUST CORP | 382K | $72.4M | -8.3% | 1.243% | 0.01% |
| 19 | AMERICAN CENTURY COMPANIES INC | 370K | $70.1M | -61.1% | 1.204% | 0.03% |
| 20 | MORGAN STANLEY | 366K | $69.4M | -37.1% | 1.191% | 0.00% |
| 21 | Boston Trust Walden Corp | 359K | $68.1M | -5.1% | 1.169% | 0.52% |
| 22 | EMERALD ADVISERS, LLC | 330K | $62.6M | +243.4% | 1.075% | 1.47% |
| 23 | UBS Group AG | 321K | $60.8M | -14.9% | 1.044% | 0.01% |
| 24 | Boston Partners | 304K | $55.7M | -10.7% | 0.989% | 0.05% |
| 25 | GOLDMAN SACHS GROUP INC | 235K | $44.6M | -52.7% | 0.766% | 0.00% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). “% of Fund” shows how much of that investor’s total 13F portfolio is invested in ACLS — a direct measure of their conviction.
Filings activity in ACLS during Q2 2026, grouped by how each filer changed its position.
8 quarters of 13F filings · Δ columns show change vs prior quarter
| Quarter | Inst. Holders | Δ Holders | Ownership % | Δ Ownership | Total 13F Value | Δ Value |
|---|---|---|---|---|---|---|
| Q2 2026 | 445 | +17% | 103.23% | 4.12 pp | $5.86B | +98% |
| Q1 2026 | 379 | +3.8% | 107.35% | +3.88 pp | $2.96B | +25% |
| Q4 2025 | 365 | +2.2% | 103.47% | +4.43 pp | $2.37B | 16% |
| Q3 2025 | 357 | +11% | 99.04% | 3.63 pp | $2.81B | +34% |
| Q2 2025 | 323 | +8.0% | 102.67% | +5.51 pp | $2.10B | +46% |
| Q1 2025 | 299 | 6.6% | 97.16% | 0.03 pp | $1.44B | 31% |
| Q4 2024 | 320 | 11% | 97.19% | +4.58 pp | $2.08B | 29% |
| Q3 2024 | 358 | — | 92.61% | — | $2.95B | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying ACLS stock.
Based on Q2 2026 13F filings, institutional ownership of Axcelis Technologies, Inc. stands at 103.2%, held across 445 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of ACLS, with approximately 5,029,462 shares worth $0.95B as of Q2 2026.
Yes — 1 widely-followed marquee investor appear among the top 25 institutional holders of ACLS, including JANE STREET GROUP, LLC.
Our composite Smart Money Score for ACLS is 49 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
105 institutions opened new positions in ACLS during Q2 2026, while 47 fully exited. 291 added to existing positions and 32 trimmed.
ACLS institutional ownership fell by 4.12 percentage points quarter-over-quarter, with a net change of +66 holders.
The top 10 institutions account for 60.3% of all reported 13F value in ACLS, and the top 25 account for 79.7%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.
Axcelis Technologies, Inc. (ACLS) Institutional Ownership