Funding profile · Chemistry AI for pharma and biotech

b12 Labs

A Y Combinator Summer 2025 company reported to have raised $500,000 in a seed round, with no Form D on file to confirm it. Here is what the aggregator reports say, and what a direct SEC search does not show.

$500KSeed round, reported by two independent trackers (Sep 2025)
$0Confirmed by SEC Form D as of this search
2Investors named: Y Combinator and Sunset Ventures
27Unrelated “B12”-named EDGAR filers checked and ruled out

Data as of September 25, 2026. Company-reported figures are labeled.

Rounds at a glance

When Round Amount Investors Source
2025 Y Combinator, Summer 2025 batch Not disclosed Y Combinator YC listing
Sep 1, 2025 Seed, as reported $500,000 Y Combinator, Sunset Ventures Aggregator report
By Oct 2025 Seed extension, in progress per one aggregator $2.8M target, not confirmed closed Not named Aggregator report

What the filings show

Nothing, as far as this search could confirm. An EDGAR company name search for “b12” returns nine entities, none of them this company: a set of Missouri and Kansas limited liability companies called B12 Equity Investments, B12 Transportation Group and Conveying Components Group, plus their numbered series. A parallel check of 27 Form D filings that separately turned up on a name match for “B12” found the same pattern: real estate and equipment-finance vehicles, a Serbian-unrelated media LLC, a quantum computing company, a financial technology company and others, none tied to b12 Labs, the chemistry AI company, or to founders Zlatko Jončev or Andres Bran. No filing under the name b-12, B-12 Inc. or b12 Labs Inc. was found.

Reading the filings

  1. The $500,000 figure has no primary source behind it.Two independent aggregator sites, AngelsRound and Startup Intros, both report a $500,000 seed round closing around September 2025 with Y Combinator and Sunset Ventures as investors. Neither is a regulatory filing or a press release from the company, and no Form D corroborates the number or the date.
  2. A company this size may not need to file yet, or may have filed under a name this search did not catch.Very early rounds, especially small ones structured as SAFEs sold to a handful of investors, are sometimes not filed at all, filed late, or filed under a holding entity with a name unrelated to the product brand. The absence of a Form D here is a gap in the public record, not proof the round did not happen.
  3. The two aggregator numbers do not obviously conflict.AngelsRound, writing in October 2025, describes a closed $500,000 pre-seed and a separate, larger $2.8 million round then being raised. Startup Intros, describing the same $500,000 as a Seed round closed in September 2025, does not mention a later round. Read together, these are consistent with a $500,000 round that closed first, followed by an attempt to raise more, rather than two conflicting accounts of the same money.
  4. Name noise is the main hazard in this company’s public record.A separate company, also commonly called B12, is a website-building platform that raised $15.7 million and shows up in the same searches. The federal grant and Form D records tied to other “B12” or “Labs”-named entities are unrelated to this company and were excluded from this profile.

Commercial signals

Signal Detail Source type
Team size Reported as two employees by one aggregator and three by a job board, as of mid to late 2026. Independent
Customers “Paid pilots with big pharma companies,” not named. Company-stated
Product claim Says a set of planned experiments achieved full conversion on the first attempt, eliminating the need for iteration. Not independently verified. Company-stated
Technical credibility Co-founder Andres Bran is the confirmed first author of the ChemCrow paper in Nature Machine Intelligence, May 2024. Public record
Compliance Company says it is SOC 2 Type 2 compliant. Not independently verified. Company-stated

What to watch

  • A first Form D under a b12 Labs or B-12 corporate entity, which is due within 15 days of a first sale of securities.
  • Confirmation, or correction, of the $500,000 seed figure by a primary source such as a company announcement or a regulatory filing.
  • Whether the $2.8 million round one aggregator described as in progress in October 2025 has closed, and at what amount.
  • Named investors beyond Y Combinator and Sunset Ventures.

The b12 Labs story on Healthcare DiscoveryHealthcare Discovery

Related companies

  • Aidy: Shared investor: Cto Fund. A free mobile app and text line that helps people with Crohn’s disease and ulcerative colitis log symptoms, diet, and biologic doses, then turns those logs into
  • PostEra: Also in Drug Discovery and Delivery. An AI chemistry company that gave its most famous work away for free
  • Convexia: Also in Drug Discovery and Delivery. A two person, Y Combinator backed startup that wants AI agents to do the job of a pharma business development team: find overlooked drugs, judge them, and eventually
  • Numerion Labs: Also in Drug Discovery and Delivery. Formerly Atomwise

Sources

  1. Public recordEDGAR company name search, “b12”SEC · accessed Sep 25, 2026
  2. Independentb-12 Labs funding and team profileAngelsRound newsletter, Ashher · Oct 1, 2025
  3. Independentb-12, Funding, Team and InvestorsStartup Intros · Jul 13, 2026
  4. IndependentB12 Raises $15.7 million (unrelated website-building company)Signalbase · Mar 24, 2026
  5. Public recordPubMed entry, PMID 38799228PubMed · accessed Sep 25, 2026
  6. Companyb12 Labs: Making hard molecules for Pharma and BiotechY Combinator company profile · accessed Sep 25, 2026
  7. Companyb12 labs websiteb12-labs.com · accessed Sep 24, 2026
  8. Companyb12 Labs company facts and job listingFreehire · Aug 18, 2026

Compiled from SEC public records and published reports as of September 25, 2026. Form D notices report offerings under Regulation D; no such filing was found for this company under the names searched. Healthcare Venture Capital Fund holds no position in b12 Labs. This page is not an offer to sell or a recommendation to buy any security.