INDEPENDENT VERDICT
01 Advisors 04, L.P. is a newly formed 2026 Delaware venture capital fund and the fourth numbered flagship vehicle in the 01 Advisors family. Its September 16 Form D sets a fixed $395 million offering under Rule 506(b) and Section 3(c)(7), but first sale has not yet occurred: the filing reports $0 sold, $395 million remaining and zero investors. The fund offers pooled investment fund interests, reports no broker, commissions, finder fees or Item 16 related-person payments, and states that the general partner or its designee is entitled to a management fee. Richard Costolo signs as Managing Partner of the general partner, while both Costolo and Adam Bain appear as related persons in the SEC governance record. The most distinctive fact is the target itself: $395 million is not merely close to the size of 01 Advisors' prior flagship—it exactly matches the publicized $395 million Fund III closed in 2023. That makes Fund IV less a story of ever-larger venture fundraising and more a test of whether 01A has intentionally settled on a repeatable fund size for its operator-led growth strategy.
THE $395M REPEAT LOOKS LIKE A STRATEGIC SIZE DECISION, NOT FUND-SIZE INFLATION
01 Advisors' fund progression gives the new filing context. Fund I began around 2019 and ultimately raised roughly $135 million, Fund II followed at about $325 million, and Fund III closed at $395 million in 2023. At that Fund III close, 01A said it remained focused primarily on Series B companies in business software and fintech after product-market fit, while David Fischer—formerly Meta's chief revenue officer—joined Dick Costolo and Adam Bain as a general partner. The latest Fund IV now returns with the exact same $395 million target rather than moving to $500 million, $600 million or another larger headline number. The Form D does not explain why the target was held flat, so it would be wrong to claim a formal capital-discipline policy from the filing alone; nevertheless, matching Fund III exactly is meaningful because fund size directly affects check size, ownership targets, portfolio count, follow-on reserves and the stage of company a manager can realistically underwrite. A fund that repeatedly writes roughly $10 million to $20 million checks into post-PMF companies may simply have less need to become a billion-dollar platform if its edge is concentrated operational involvement rather than sheer capital scale.
01A'S REAL DIFFERENTIATOR IS THAT ITS PARTNERS BUILT GTM MACHINES BEFORE BECOMING INVESTORS
01 Advisors' public positioning is unusually specific for a venture firm. Its own materials describe the strategy as "For Operators, by Operators" and emphasize that its senior team previously scaled companies from near-zero to enormous revenue bases: Costolo led Twitter as CEO, Bain built Twitter's revenue and advertising organization as COO and president, and Fischer spent more than a decade at Facebook/Meta, ultimately serving as chief revenue officer after earlier work helping build Google's sales infrastructure. The firm says it generally invests after companies have achieved product-market fit, typically around late Series A and Series B, and focuses on scaling go-to-market, revenue organizations, recruiting and operating systems rather than trying to identify raw pre-seed technical ideas. That model also explains why Fund IV size matters. A manager whose value proposition depends on concentrated hands-on engagement can dilute its own advantage if it expands fund size faster than the team's ability to work deeply with portfolio companies, making a repeated $395 million pool potentially more consistent with the stated strategy than a much larger fund would be.
THE PORTFOLIO HISTORY SHOWS WHY 01A IS NOT SIMPLY A "FORMER TWITTER EXEC" BRAND
01A's prior portfolio provides evidence that the strategy has extended beyond social media despite the founders' backgrounds. Publicly associated investments include companies such as Tipalti, SpotOn, HoneyBook and Linear, while the firm's current portfolio jobs network spans dozens of companies and more than a thousand open roles. The firm's historical thesis has emphasized B2B software, fintech and companies entering rapid scaling phases where distribution, pricing, sales leadership and organizational design become bottlenecks. That matters because Fund IV should not automatically be characterized as an "AI fund" simply because the 2026 venture market is dominated by AI headlines, nor should every current portfolio company be attributed to the new vehicle before investments are publicly identified. The Form D gives no portfolio, no first sale and no capital commitments yet. The cleaner diligence framework is to track whether Fund IV maintains the same post-PMF discipline or broadens into larger later-stage rounds as valuations and check requirements increase.
THE BIGGEST QUESTION IS WHETHER $395M STILL BUYS THE SAME OWNERSHIP IT DID IN 2023
Flat nominal fund size does not mean flat economic capacity. Since Fund III closed in 2023, private-company valuations—especially in AI infrastructure, developer tooling and high-growth enterprise software—have changed dramatically. If 01A still wants meaningful ownership in companies after product-market fit, the same $10 million to $20 million check may purchase a smaller percentage of the best companies than it did three years earlier. Fund IV therefore creates a useful test: will 01A keep its historical check discipline and accept smaller ownership, concentrate capital into fewer investments, syndicate more heavily with larger funds, or move selectively into companies where operational help earns access at attractive prices Investors should ask for the planned number of core investments, initial and follow-on reserve ratios, target ownership, recycling provisions, concentration limits, management fee and carry, and whether Fund IV's construction materially differs from Fund III. The Form D itself only proves a $395 million target and management-fee entitlement; it does not prove that any LP has committed, that the target will be reached or that past portfolio performance will repeat.
FINAL ASSESSMENT
01 Advisors Fund IV is unusual precisely because the filing is not dramatic on the surface. SEC EDGAR confirms a new $395 million Venture Capital Fund, Rule 506(b), Section 3(c)(7), $0 sold, zero investors and first sale yet to occur. But the number becomes meaningful when placed next to the firm's history: Fund III was also $395 million, and 01A publicly built its reputation around staying close to a specific post-product-market-fit operating problem rather than becoming a broad multi-strategy asset manager. The strongest independent interpretation is therefore that Fund IV may represent an attempt to repeat a proven fund-construction model rather than maximize headline AUM. Whether that discipline holds will become visible only when the first sale appears, LP count develops and the initial Fund IV investments can be compared with Fund III's portfolio. Until then, $395 million is a target, not capital raised.
Form D is an exempt-offering notice. It is not SEC approval of 01 Advisors, Fund IV, Dick Costolo, Adam Bain, any portfolio company or any projected investment return.
SEC SNAPSHOT
ISSUER: 01 Advisors 04, L.P. | CIK: 0002115466 | SEC FILE NO.: 021-597744 | FILM NO.: 261384043 | ACCESSION NO.: 0001231919-26-001189 | FILED / EFFECTIVE: September 16, 2026
ENTITY: Delaware Limited Partnership | FORMED: 2026 | ADDRESS: 415 Jackson Street, 3rd Floor, San Francisco, CA 94111 | PHONE: 510-213-8185
INDUSTRY: Pooled Investment Fund - Venture Capital Fund | EXEMPTION: Regulation D Rule 506(b) | INVESTMENT COMPANY ACT: Section 3(c)(7)
SECURITY: Pooled Investment Fund Interests | FIRST SALE: Yet to occur | OFFERING DURATION: One year or less
TOTAL OFFERING: $395,000,000 | AMOUNT SOLD: $0 | REMAINING: $395,000,000 | INVESTORS: 0 | MINIMUM INVESTMENT FIELD: $0
GENERAL PARTNER: 01 Advisors 04 GP LLC
RELATED PERSONS: Richard Costolo — Managing Partner of GP | Adam Bain — Managing Partner of GP
FORM D SIGNATORY: Richard Costolo | TITLE: Managing Partner of the General Partner of the Issuer
MANAGEMENT FEE: Form D states that the General Partner or its designee is entitled to a management fee payable by the fund. Exact fee and carry terms are not disclosed.
SALES COMMISSIONS: $0 | FINDER FEES: $0 | ITEM 16 RELATED-PERSON PAYMENTS: $0 | NAV: Declined to disclose
PUBLIC FIRM STRATEGY: 01 Advisors describes itself as an operator-led venture firm investing after product-market fit, primarily in late Series A and Series B companies, with typical public check-size guidance around $10M-$20M.
FUND HISTORY: 01 Advisors 01 — approximately $135M scale | 01 Advisors 02 — approximately $325M | 01 Advisors 03 — publicly closed at $395M in 2023 | 01 Advisors 04 — new 2026 SEC target of $395M.
IMPORTANT FUND-SIZE DISTINCTION: Fund IV's $395M is an OFFERING TARGET. The latest SEC filing reports $0 sold and zero investors. It must not be described as a $395M fund close or $395M raised.
UNIQUE STRUCTURAL FINDING: Fund IV targets exactly the same headline size as Fund III rather than continuing the rapid size expansion seen from Fund I to Fund II and Fund III. The public record does not disclose whether this was an intentional size cap, but it creates a test of whether 01A is preserving a repeatable post-PMF portfolio construction model instead of pursuing fund-size growth for its own sake.
CORE INDEPENDENT FINDING: 01 Advisors Fund IV is best understood as a "repeat-the-machine" filing rather than a bigger-is-better fundraising story. The firm's operating thesis, typical check size and concentrated scale-up support may place a practical ceiling on useful fund size. The key diligence question is whether a $395M vehicle still provides sufficient ownership economics in the 2026 venture market while allowing Costolo, Bain, Fischer and the broader team to maintain the hands-on operating model that differentiates 01A.
Form D is an exempt-offering notice and is not an SEC-issued certificate, approval or endorsement.