Russell Quarterly IPO Additions, September 2026: The Full Preliminary List, With $QNT, $FRVO, $HAWK and $COAG as Worked Examples

Executive Summary

Four times a year — in March, June, September and December — FTSE Russell adds eligible newly public companies to the Russell US Indexes outside of the semi-annual reconstitution. On August 21, 2026, FTSE Russell published the preliminary lists for the September 2026 quarterly IPO review: 36 distinct tickers are set to join the Russell 1000, Russell 2000 and/or Russell Microcap Index, effective at the open of trading on September 21, 2026.

This matters to traders because index inclusion is not discretionary. Every ETF and index fund benchmarked to the Russell family — collectively tens of trillions of dollars — must buy the newly added names by the effective date, regardless of their own view on the stock. For a company that only listed a few months ago and still has thin trading volume, that mechanical demand can be a meaningful event.

This article breaks down how the quarterly IPO addition process works, who is on the preliminary list this time — including several names directly relevant to biotech, space/defense and critical-minerals investors — and what has historically happened to small caps around this kind of index event. Every company detail below is sourced to a primary filing, an official press release, or a top-tier financial outlet; where a figure could not be independently confirmed, it is flagged rather than assumed.

What the Quarterly IPO Addition Actually Is

It is easy to confuse this event with the better-known Russell Reconstitution, the semi-annual rebalance (June and December) that resets the entire index membership based on a single “Rank Day” snapshot. The quarterly IPO addition is a separate, narrower mechanism: FTSE Russell allows newly public companies to enter the Russell 3000, Russell 1000, Russell 2000 or Russell Microcap Index in March, June, September and December, rather than making them wait up to a year for the next full reconstitution.

The logic is straightforward. Dozens of companies go public every quarter. If the Russell indexes only updated once or twice a year, a large newly listed company could sit outside every major benchmark for months — even though institutional and retail capital is already trading it daily. Quarterly IPO additions close that gap. Since the mechanism was introduced in September 2004, FTSE Russell has added more than 2,500 IPOs through this process, the large majority into the Russell 2000.

Separately, FTSE Russell also runs an IPO Fast Entry rule for exceptionally large listings: a company large enough to rank inside the Russell Top 500 can be added within days of its IPO, without waiting for the next quarterly window at all. None of the names on this September 2026 list qualified for fast entry — all 36 are going through the standard quarterly review.

How It Works: From Preliminary List to Effective Date

FTSE Russell’s own methodology describes quarterly IPO additions for the March and September cycles as being announced on the Friday four weeks ahead of implementation, with the change effective after the close of the third Friday of the review month. The September 2026 cycle follows that framework:

• August 21, 2026
  Preliminary lists published. FTSE Russell posts the Russell 1000, Russell 2000 and Russell Microcap preliminary IPO addition PDFs. This is the moment the market first sees who is likely to be added.
• August 21 – September 4, 2026
  Query period. The window during which the preliminary data can be challenged or corrected by market participants and issuers before the list is treated as final.
• September 7, 2026
  Lock-down begins. From this date, the list of additions is considered final barring extraordinary corporate events (a delisting, an acquisition closing, a bankruptcy filing).
• September 21, 2026
  Effective date. The 36 additions become live in the Russell 1000, Russell 2000 and Russell Microcap Indexes at the open of US trading. Every fund benchmarked to these indexes must hold the new constituents from this point forward.

What Index Inclusion Has Historically Meant for a Stock

The Russell family of indexes is one of the most widely benchmarked in the US equity market, tracked by a broad mix of index funds, ETFs and pension mandates. Because inclusion is rules-based and non-discretionary, entering a Russell index creates a predictable — though not guaranteed — set of mechanical effects.

1. Mechanical, forced buying

Funds that replicate the Russell 2000, Russell 1000 or Russell 3000 do not choose whether to buy a newly added stock — they are required to, in proportion to its index weight, by the effective date. For a company that only IPO’d a few months ago with a thin public float, that demand can represent several days or weeks of ordinary trading volume compressed into a short window around September 21.

2. A step up in institutional visibility

Once a stock is inside a Russell index, it appears on the screens of every portfolio manager and analyst who benchmarks against that index. This tends to translate into incremental sell-side coverage and a broader base of potential institutional buyers over time.

3. A frequently observed pre-effective-date “run-up”

Market participants who track index-rebalance flows often position ahead of the effective date once the preliminary list is public — this is legal and is simply a function of publicly available information, not a signal of anything company-specific. This anticipatory positioning is a documented pattern around Russell Reconstitution and, to a lesser degree, around quarterly IPO additions; it does not apply uniformly to every name and tends to be more pronounced for smaller, thinly traded stocks.

4. A structural liquidity improvement

Beyond the days surrounding the effective date, the more durable effect is liquidity: a stock inside the Russell 2000 or Russell Microcap is bought and sold every day by dozens of replicating funds, which over time tends to narrow bid-ask spreads and support higher average trading volume.

The Full Preliminary List: All 36 Names

Source for ticker, company name and index assignment: FTSE Russell / LSEG official preliminary IPO addition PDFs for Q3 2026 (Russell 1000, Russell 2000, Russell Microcap), data as at August 21, 2026, effective September 21, 2026. Company business descriptions, exchange, IPO date and offering size below were verified separately against SEC filings (S-1, 424B4, 8-K), official company/IR press releases, or top-tier financial press — sources are cited in each entry and in the Sources section at the end of this article. Twelve tickers appear on both the Russell 2000 and Russell Microcap preliminary lists, reflecting overlapping market-cap eligibility ranges between the two indexes.

Russell 1000 (large cap) — 4 additions

Russell 2000 (small cap) — 27 additions

Russell Microcap — 5 additional unique names

Twelve of the Russell 2000 names above (Seaport Therapeutics, Apnimed, Forbright, Reformation, Odyssey Therapeutics, WhiteHawk, GMR Solutions, First Carolina Financial, Mobia Medical, Scribe Therapeutics, Suja Life, Rare Earths Americas) also appear on the Russell Microcap preliminary list, reflecting the overlapping market-cap band between the two indexes. The five names below appear only on the Microcap list.

Sector Focus: Biotech Is the Largest Bucket on This List

Eight of the 36 additions are biotech or healthcare names — the single largest sector grouping in this cycle, consistent with 2026 being a record year for biotech IPO volume. Two deals stand out by size: $PBLS Parabilis Medicines raised roughly $670 million in an upsized Nasdaq listing backed by a concurrent Regeneron private placement, and $COAG Hemab Therapeutics, a Novo Holdings portfolio company, priced an upsized $346.7 million offering around a Breakthrough Therapy-designated program for rare bleeding disorders.

The mechanisms and modalities span a wide range: gene editing ($SCTX Scribe Therapeutics, CRISPR for cardiometabolic targets including PCSK9/Lp(a)), CNS drug development ($SPTX Seaport Therapeutics), autoimmune and inflammatory disease ($ODTX Odyssey Therapeutics, whose lead program is studied alongside Takeda’s Entyvio), sleep medicine ($APMD Apnimed, developing what would be the first oral pill for obstructive sleep apnea, with an FDA decision expected in February 2027), and medtech ($MOBI Mobia Medical’s FDA-approved Vivistim stroke-rehabilitation device).

Sector Focus: Space, Defense and Critical Minerals

Beyond biotech, this cycle’s list touches two other Merlintrader coverage areas directly. $HAWK HawkEye 360 — a satellite-based radiofrequency intelligence company supplying data to US and allied defense and security customers — raised $416 million pricing at the top of its range, with the stock opening roughly 30% above the IPO price. $AADX Applied Aerospace & Defense raised $650 million for aerospace and defense subsystem manufacturing.

On critical minerals, $EMAT Evolution Metals & Technologies is the standout: it is the only company on this entire list that has independently confirmed, in its own August 24, 2026 press release and accompanying SEC 8-K, its preliminary inclusion in the Russell 3000 and Russell 2000 indexes effective September 21, 2026 — an unusually direct, company-level corroboration of the FTSE Russell data. The list also includes $SSMR Sunshine Silver Mining & Refining (an integrated silver mine-mill-refinery project in Idaho) and $REA Rare Earths Americas (heavy rare earth exploration in Brazil and Georgia, USA), both relevant to the critical-minerals supply-chain theme that has driven a wave of 2026 mining IPOs.

What Is Verified, and What Is Not

In keeping with our editorial standard of citing a primary source for every material claim, here is an explicit account of the verification behind this list:

The list itself — ticker, company name, and target index — is sourced directly from FTSE Russell’s own preliminary IPO addition PDFs, published by LSEG on August 21, 2026 and downloaded directly from lseg.com. This is the official index provider’s own document, which is as close to a primary source as this type of data gets.

Company-level business descriptions, IPO pricing, offering size and listing dates were separately verified against SEC filings (S-1, 424B4, 8-K), official company or investor-relations press releases, and top-tier financial media (CNBC, Bloomberg, Reuters-affiliated outlets, FierceBiotech, BioPharma Dive, MedCity News, Mining.com), with sources cited in the table above and consolidated below. For two names — $ITG and $FRBT — pricing figures could only be confirmed through secondary financial-data outlets (StreetInsider, TradingView News, Investing.com) rather than an original company press release; readers should treat those two specific figures with slightly lower confidence pending a primary-source cross-check.

What could not be independently verified: a separate, company-issued confirmation of Russell inclusion for 35 of the 36 names (only $EMAT has published one). This is normal — most companies do not issue a press release confirming index inclusion — but it means the sole source for those 35 names’ inclusion is the FTSE Russell document itself, not a second, independent corroboration.