Private company
Who owns Spear Bio
One company in the researched set discloses a stake in Spear Bio, worth $15m between them. Spear Bio is private, so no 13F reports it: a 13F covers exchange listed positions only. These figures exist because each holder disclosed the stake in its own filings.
Spear Bio - Profile
- Type
- private company
- Based in
- United States
- Founded
- 2021
Spear Bio is a life science company in Woburn, Massachusetts that develops ultrasensitive protein detection assays for biomedical research and diagnostics. Its SPEAR platform, short for Successive Proximity Extension Amplification Reaction and licensed from Harvard University, converts an antibody binding event into a DNA signal that is read on ordinary qPCR instruments, which the company says gives sensitivity two to three orders of magnitude beyond conventional immunoassays without specialised hardware. The initial products measure blood biomarkers of neurodegeneration, including phosphorylated tau 217, phosphorylated tau 231, GFAP and neurofilament light, with further work aimed at inflammation and oncology. Founded in 2021, the company raised a 45 million dollar Series A in 2024 and in 2025 agreed a distribution partnership that puts its assays into a larger reagent supplier's catalogue.
Source
Spear Bio files nothing with the SEC, so none of this comes from a filer record. The description was written for this site in August 2026 from Spear Bio Announces Strategic Partnership with Bio-Techne (Spear Bio), Bio-Techne and Spear Bio Announce Strategic Partnership to Advance Therapeutic Development with Ultrasensitive Biomarker Detection (Bio-Techne investor relations) and Bio-Techne to distribute Spear Bio's ultrasensitive immunoassays (Medical Device Network). The ownership figures below come from the holders' filings instead, and are sourced row by row.
The disclosed stakes
One row per position. Where a holder reports the same company in two share classes, both rows are shown rather than summed, because the class is part of a position's identity.
Where each figure comes from
A private stake has no ownership form behind it, so the source is always the holder's own filing or disclosure. Anything modelled says so, with the arithmetic.
- Bio-Techne Corporation, as of 31 Mar 2026. In July 2024 Bio-Techne paid $15 million to enter an investment in Spear Bio, a private company, accounted for under the cost method because the filing states Bio-Techne owns 'less than 20% of the outstanding stock' and does not have significant influence. The 10-Q gives only that upper-bound qualitative statement, never an exact percentage or share count, so per the project's rule against inventing a number pct_of_target is left null rather than assumed at, e.g., 19.9% (the Wilson Wolf figure). The $15,000 thousand carrying value shown in Other Assets as of 31 Mar 2026 is unchanged from 30 Jun 2025 and from the original July 2024 investment (no further investment made in fiscal 2026 per the cash flow statement, and under the cost method the fair value is only re-estimated if a triggering event/change in circumstances occurs, none of which had been identified as of 31 Mar 2026). source
What this page is not
It is not a complete register. It lists the holders who happen to be inside the researched set and disclosed the stake themselves. A private company can have many other shareholders, and nothing here rules them out: venture investors, founders and employees usually appear in no public filing at all. Percentages are of Spear Bio where a holder stated one, and are missing where no holder did.