Among active 13F managers last quarter, 2 added and none reduced or exited; the largest holder to move was Tower Research Capital LLC (TRC) (+32%). Over the last 180 days, 3 insiders bought and none sold, a net $0 in open-market trades.
Funds lean in and no leg opposes.
14 tracked 13F filers disclose a position in MBRX as of the latest SEC 13F filings, a combined $358K in reported value. Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
| # | Fund | Shares | Position value | Last move | As of | History |
|---|---|---|---|---|---|---|
| 1 | Geode Capital Management, LLC | 47K | $132K | ▲+46% Added · +15K sh | Q2 2026 | |
| 2 | Vanguard Capital Management LLC | 42K | $118K | ▲+204% Added · +28K sh | Q2 2026 | |
| 3 | Vanguard Fiduciary Trust Co | 30K | $83K | ▲+392% Added · +24K sh | Q2 2026 | |
| 4 | Rockefeller Capital Management L.P. | 4K | $10K | ▲20× Added · +4K sh | Q1 2026 | |
| 5 | UBS Group AG | 3K | $8K | ▼−42% Reduced · −2K sh | Q1 2026 | |
| 6 | Tower Research Capital LLC (TRC) | 2K | $4K | ▲+32% Added · +442 sh | Q1 2026 | |
| 7 | BlackRock, Inc. | 491 | $1K | —Held | Q2 2026 | |
| 8 | EFG International AG | 434 | $1K | —Held | Q2 2026 | |
| 9 | NFSG Corp | 114 | $318 | —Held | Q2 2026 | |
| 10 | SBI Securities Co., Ltd. | 44 | $123 | ▲+2.3% Added · +1 sh | Q2 2026 | |
| 11 | Morgan Stanley | 36 | $83 | —Held | Q1 2026 | |
| 12 | Danske Bank A/s | 2 | $6 | —Held | Q2 2026 | |
| 13 | CVA Family Office, LLC | 1 | $3 | —Held | Q2 2026 | |
| 14 | Osaic Holdings, Inc. | 1 | $2 | —Held | Q1 2026 |
Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.
Last quarter, 2 funds added to an existing position in MBRX, while none reduced or exited. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).
| Company | Co-held by | Their position there |
|---|---|---|
| Nvidia CorpNVDA | 5 funds | $873.7M |
| Apple IncAAPL | 5 funds | $472.4M |
| Microsoft CorpMSFT | 5 funds | $401.9M |
| Amazon.com IncAMZN | 5 funds | $350.5M |
| Invesco QQQ Trust Series 1QQQ | 5 funds | $327.1M |
| Vanguard S&P 500 ETFVOO | 5 funds | $316.5M |
| Alphabet Inc-CL AGOOGL | 5 funds | $266.3M |
| Alphabet Inc-CL CGOOG | 5 funds | $250.0M |
| Micron Technology IncMU | 5 funds | $249.5M |
| Broadcom IncAVGO | 5 funds | $239.3M |
| Tesla IncTSLA | 5 funds | $218.1M |
| Applied Materials IncAMAT | 5 funds | $195.8M |
Ranked by how many of MBRX's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in MBRX.
| Date | Insider | Role | Action | Shares | Value |
|---|---|---|---|---|---|
| Aug 3, 2026 | Foster Jonathan P. | Chief Financial Officer | Buy (P) | 293K | — |
| Aug 3, 2026 | Klemp Walter V | CEO and President, Director | Buy (P) | 533K | — |
| Aug 3, 2026 | Picker Donald H | Chief Science Officer | Buy (P) | 173K | — |
| Jun 23, 2025 | Klemp Walter V | CEO and President, Director | Buy (P) | 676K | $250K |
| Jun 23, 2025 | Foster Jonathan P. | Chief Financial Officer | Buy (P) | 270K | $100K |
| Dec 26, 2023 | Klemp Walter V | CEO and President, Director | Buy (P) | 188K | $130K |
| Dec 26, 2023 | George Robert E. | Director | Buy (P) | 14K | $10K |
| Dec 26, 2023 | Foster Jonathan P. | Chief Financial Officer | Buy (P) | 29K | $20K |
| Nov 25, 2022 | Klemp Walter V | CEO and President, Director | Buy (P) | 45K | $58K |
| Nov 21, 2022 | Klemp Walter V | CEO and President, Director | Buy (P) | 23K | $26K |
| Nov 17, 2022 | Klemp Walter V | CEO and President, Director | Buy (P) | 25K | $25K |
| Nov 16, 2022 | Klemp Walter V | CEO and President, Director | Buy (P) | 85K | $83K |
Where institutional funds (13F), corporate insiders (Form 4) and US House members (STOCK Act) are buying or selling the same name in the same window. Green is buying, red is selling.
Insiders and Congress: last 180 days. Funds: latest 13F, top 100 holders incl. passive
| Source | Buying | Selling | Net |
|---|---|---|---|
13F funds Top 100 holders by value, passive included; the hero counts active managers only | 6 | 1 | – |
Insiders Form 4 open-market | 3 | 0 | $0 |
US House STOCK Act trades | 0 | 0 | $0 |
Capital Rotation reports where institutional capital disclosed rotating, as of the latest public SEC 13F filings. It is data, not investment advice, a recommendation, or a prediction. Filings lag about 45 days and cover long US equity positions only. Past disclosed flows do not indicate future prices. Do your own research; consult a licensed advisor.
Connected entities for MBRX
This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/stocks/MBRX/capital-change-brief"
Use Arkolith's capital_change_brief for MBRX. Tell me what changed, whether insider activity corroborates it, and cite the SEC evidence.
13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for MBRX. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.