Axcelis Technologies, Inc. (ACLS) Ownership
ACLS ownership summary
as of October 18, 2026- Institutions
- 103.6% of shares outstanding
- Insiders
- 0.68% of shares outstanding
- Shares outstanding
- 30.9M
- Float
- 30.7M shares available to trade
- Short interest
- 6.72% 1.4M shares short
- Days to cover
- 4.07 short interest up 0.3% vs prior month
- Institutions 103.64%
- Insiders 0.68%
ACLS top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 16.29% | 5.0M | $544.9M | +92,688 (+1.9%) | June 30, 2026 |
| 2 | FMR Inc | 13.36% | 4.1M | $447.0M | +1.7M (+69.7%) | June 30, 2026 |
| 3 | Vanguard Portfolio Management, LLC | 8.03% | 2.5M | $268.6M | −9,415 (−0.4%) | June 30, 2026 |
| 4 | Vanguard Capital Management, LLC | 4.49% | 1.4M | $150.2M | +3,748 (+0.3%) | June 30, 2026 |
| 5 | State Street Corp | 3.99% | 1.2M | $133.4M | +42,064 (+3.5%) | June 30, 2026 |
| 6 | Victory Capital Management Inc. | 3.67% | 1.1M | $122.9M | −144,998 (−11.3%) | June 30, 2026 |
| 7 | Reinhart Mahoney Capital Management Inc | 3.43% | 1.1M | $114.9M | +131,976 (+14.2%) | September 30, 2026 |
| 8 | Geode Capital Management, LLC | 2.70% | 834K | $90.3M | +22,343 (+2.8%) | June 30, 2026 |
| 9 | BNP Paribas Investment Partners SA | 2.60% | 803K | $87.0M | −202,877 (−20.2%) | June 30, 2026 |
| 10 | Dimensional Fund Advisors, Inc. | 2.30% | 709K | $76.8M | −134,831 (−16.0%) | June 30, 2026 |
| 11 | Balyasny Asset Management LLC | 2.00% | 616K | $66.8M | −748,344 (−54.8%) | June 30, 2026 |
| 12 | PRIMECAP Management Company | 1.98% | 610K | $66.1M | −48,201 (−7.3%) | June 30, 2026 |
| 13 | Amvescap Plc. | 1.71% | 528K | $57.2M | +362,649 (+219.7%) | June 30, 2026 |
| 14 | Charles Schwab Investment Management Inc | 1.35% | 416K | $45.1M | −29,539 (−6.6%) | June 30, 2026 |
| 15 | T. Rowe Price Associates, Inc. | 1.28% | 394K | $42.7M | +32,253 (+8.9%) | June 30, 2026 |
| 16 | Barrow Hanley Mewhinney & Strauss LLC | 1.27% | 392K | $42.5M | +392,183 (+688,040.4%) | June 30, 2026 |
| 17 | Manufacturers Life Insurance Co | 1.24% | 384K | $41.6M | −107,985 (−22.0%) | June 30, 2026 |
| 18 | Northern Trust Corp | 1.24% | 382K | $41.4M | −34,676 (−8.3%) | June 30, 2026 |
| 19 | American Century Companies Inc | 1.20% | 370K | $40.1M | −582,035 (−61.1%) | June 30, 2026 |
| 20 | Morgan Stanley - Brokerage Accounts | 1.19% | 366K | $39.7M | −215,559 (−37.1%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 9 holders added 2.8M shares and 11 cut 2.3M.
ACLS top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | iShares Core S&P Small-Cap ETF | 5.95% | 1.8M | $199.2M | +408 (+0.0%) | September 30, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 3.17% | 979K | $106.1M | −1,244 (−0.1%) | August 31, 2026 |
| 3 | Amundi Fds Global Equity A EUR C | 3.09% | 955K | $103.4M | +37,290 (+4.1%) | August 31, 2026 |
| 4 | iShares Russell 2000 ETF | 2.64% | 816K | $88.4M | −9,408 (−1.1%) | September 30, 2026 |
| 5 | Vanguard Information Technology ETF | 2.41% | 745K | $80.7M | +1,716 (+0.2%) | September 30, 2026 |
| 6 | Vanguard Small Cap Index | 2.25% | 695K | $75.3M | −11,331 (−1.6%) | September 30, 2026 |
| 7 | PRIMECAP Odyssey Aggressive Growth | 1.88% | 580K | $62.8M | −36,085 (−5.9%) | June 30, 2026 |
| 8 | Vanguard MStar Small Cap Value Index | 1.47% | 452K | $49.0M | +3,316 (+0.7%) | September 30, 2026 |
| 9 | Fidelity Contrafund | 1.33% | 412K | $44.6M | −135 (−0.0%) | August 31, 2026 |
| 10 | Strategic Advisers Fidelity US TtlStk | 1.31% | 405K | $43.9M | +34,709 (+9.4%) | August 31, 2026 |
| 11 | Fidelity Stock Selector Small Cap | 1.15% | 354K | $38.3M | −43,300 (−10.9%) | July 31, 2026 |
| 12 | Fidelity Small Cap Index | 1.11% | 343K | $37.2M | +2,888 (+0.8%) | July 31, 2026 |
| 13 | BNP Paribas Disrpt Tech Cl D | 1.07% | 331K | $35.9M | −51,364 (−13.4%) | August 31, 2026 |
| 14 | iShares Russell 2000 Growth ETF | 0.95% | 294K | $31.9M | −372 (−0.1%) | September 30, 2026 |
| 15 | Fidelity Small Cap Discovery | 0.91% | 281K | $30.4M | +21,125 (+8.1%) | July 31, 2026 |
| 16 | State Street SPDR Port S&P 600 Sm CpETF | 0.91% | 280K | $30.4M | — | September 30, 2026 |
| 17 | Fidelity Value | 0.90% | 279K | $30.2M | — | August 31, 2026 |
| 18 | BNP Paribas US Small Cap ClassicC | 0.86% | 264K | $28.6M | −9,746 (−3.6%) | August 31, 2026 |
| 19 | Fidelity Series Small Cap Opps | 0.78% | 241K | $26.1M | −29,100 (−10.8%) | July 31, 2026 |
| 20 | Fidelity Series Small Cap Discovery | 0.76% | 235K | $25.4M | +8,238 (+3.6%) | July 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
ACLS insider transactions
latest 5| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-01 | Russell Low | Sell | $94.06 | 1,244 | $117,011 |
| 2026-02-20 | Jorge Titinger | Sell | $80.00 | 1,000 | $80,000 |
| 2025-12-17 | Jorge Titinger | Sell | $86.05 | 2,000 | $172,100 |
| 2025-12-11 | Gerald M Blumenstock | Sell | $89.46 | 3,034 | $271,422 |
| 2025-05-20 | John T Kurtzweil | Sell | $61.93 | 1,682 | $104,166 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
ACLS shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns ACLS
Institutional investors own 103.6% of Axcelis Technologies's shares and insiders 0.68%. The largest holder is BlackRock Inc with 16.29% of the shares (5.0M), as of June 30, 2026. Among the top 20 institutions, 9 added shares and 11 reduced their stake in the latest filings. Short interest is 6.72% of the float, or 4.07 days of average trading volume. The share count rose 6.2% since 2014.
Related: ACLS analyst forecast, ACLS key metrics. See the ACLS stock overview for the latest quote and news.
ACLS ownership FAQ
Who owns the most Axcelis Technologies stock?
The largest shareholders of Axcelis Technologies are BlackRock Inc (16.29%), FMR Inc (13.36%), Vanguard Portfolio Management, LLC (8.03%), Vanguard Capital Management, LLC (4.49%), State Street Corp (3.99%).
What percentage of Axcelis Technologies is owned by institutions?
Institutions hold 103.6% of Axcelis Technologies's shares outstanding; insiders hold 0.68%.
Which funds own Axcelis Technologies?
The largest fund holders of Axcelis Technologies are iShares Core S&P Small-Cap ETF (5.95%), Vanguard MStar Total Stk Mkt Idx Invest (3.17%), Amundi Fds Global Equity A EUR C (3.09%), iShares Russell 2000 ETF (2.64%), Vanguard Information Technology ETF (2.41%).
What is Axcelis Technologies's short interest?
1.4M shares of Axcelis Technologies were sold short, 6.72% of the float; at the average daily volume it would take 4.07 days to cover.
Are insiders buying or selling Axcelis Technologies?
Of the latest 5 reported insider transactions in Axcelis Technologies (since May 20, 2025), 0 were purchases and 5 were sales.
How many shares of Axcelis Technologies are outstanding?
Axcelis Technologies has 30.9M shares outstanding, of which 30.7M are in the public float.