Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in OABI held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | Whitefort Capital Management, LP | 14.2M | $22.3M | 0.0% | 11.944% | 6.80% |
| 2 | BlackRock, Inc. | 8.1M | $12.7M | +0.5% | 6.807% | 0.00% |
| 3 | CADIAN CAPITAL MANAGEMENT, LP | 4.2M | $6.5M | -6.3% | 3.491% | 0.79% |
| 4 | VANGUARD CAPITAL MANAGEMENT LLC | 4.0M | $6.3M | — | 3.354% | 0.00% |
| 5 | GEODE CAPITAL MANAGEMENT, LLC | 2.9M | $4.6M | +7.4% | 2.457% | 0.00% |
| 6 | RICE HALL JAMES & ASSOCIATES, LLC | 2.5M | $4.0M | +6.1% | 2.139% | 0.22% |
| 7 | PRIVATE MANAGEMENT GROUP INC | 2.4M | $3.8M | +0.4% | 2.040% | 0.11% |
| 8 | STATE STREET CORP | 2.1M | $3.2M | +0.9% | 1.736% | 0.00% |
| 9 | DIMENSIONAL FUND ADVISORS LP | 1.7M | $2.7M | -18.9% | 1.466% | 0.00% |
| 10 | TOWERVIEW LLC | 1.0M | $1.6M | 0.0% | 0.840% | 1.01% |
| 11 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 960K | $1.5M | -0.7% | 0.806% | 0.00% |
| 12 | VANGUARD PORTFOLIO MANAGEMENT LLC | 904K | $1.4M | — | 0.759% | 0.00% |
| 13 | NORTHERN TRUST CORP | 881K | $1.4M | +6.3% | 0.740% | 0.00% |
| 14 | ISTHMUS PARTNERS, LLC | 757K | $1.2M | +4.9% | 0.635% | 0.12% |
| 15 | VANGUARD FIDUCIARY TRUST CO | 726K | $1.1M | — | 0.609% | 0.00% |
| 16 | ADAR1 Capital Management, LLC | 705K | $1.1M | +0.4% | 0.592% | 0.07% |
| 17 | NOMURA HOLDINGS INC | 705K | $1.1M | +355.0% | 0.592% | 0.00% |
| 18 | Nuveen, LLC | 624K | $979K | -28.7% | 0.524% | 0.00% |
| 19 | TWO SIGMA INVESTMENTS, LP | 513K | $805K | +21.2% | 0.430% | 0.00% |
| 20 | GOLDMAN SACHS GROUP INC | 419K | $658K | -22.4% | 0.352% | 0.00% |
| 21 | MORGAN STANLEY | 408K | $640K | +4.7% | 0.343% | 0.00% |
| 22 | MILLENNIUM MANAGEMENT LLC | 524K | $630K | -22.2% | 0.440% | 0.00% |
| 23 | D. E. Shaw & Co., Inc. | 380K | $597K | -0.8% | 0.319% | 0.00% |
| 24 | EverSource Wealth Advisors, LLC | 11K | $550K | +424.7% | 0.009% | 0.02% |
| 25 | Bank of New York Mellon Corp | 274K | $431K | +2.2% | 0.231% | 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 OABI — a direct measure of their conviction.
Filings activity in OABI during Q1 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 |
|---|---|---|---|---|---|---|
| Q1 2026 | 126 | +0.0% | 32.37% | 6.60 pp | $88M | 17% |
| Q4 2025 | 126 | 8.0% | 38.97% | +2.16 pp | $105M | +5.9% |
| Q3 2025 | 137 | 4.9% | 36.81% | +1.84 pp | $100M | +5.3% |
| Q2 2025 | 144 | 5.3% | 34.97% | 20.48 pp | $95M | 37% |
| Q1 2025 | 152 | 6.2% | 55.45% | 26.22 pp | $150M | 32% |
| Q4 2024 | 162 | +0.6% | 81.67% | 38.82 pp | $221M | 32% |
| Q3 2024 | 161 | +1.9% | 120.49% | +14.58 pp | $326M | +14% |
| Q2 2024 | 158 | — | 105.91% | — | $286M | — |
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 OABI stock.
Based on Q1 2026 13F filings, institutional ownership of OmniAb, Inc. stands at 32.4%, held across 126 reporting institutions.
Whitefort Capital Management, LP is the largest reported institutional holder of OABI, with approximately 14,223,658 shares worth $0.02B as of Q1 2026.
Yes — 2 widely-followed marquee investors appear among the top 25 institutional holders of OABI, including TWO SIGMA INVESTMENTS, LP, MILLENNIUM MANAGEMENT LLC.
Our composite Smart Money Score for OABI is 45 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
25 institutions opened new positions in OABI during Q1 2026, while 25 fully exited. 23 added to existing positions and 77 trimmed.
OABI institutional ownership fell by 6.60 percentage points quarter-over-quarter, with a net change of +0 holders.
The top 10 institutions account for 77.5% of all reported 13F value in OABI, and the top 25 account for 93.7%.
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.
OmniAb, Inc. (OABI) Institutional Ownership