The Form F-1MEF Files Dataset is a complete corpus of EDGAR submissions of Form F-1MEF — the abbreviated Rule 462(b) registration statement that a foreign private issuer files to add up to 20% additional securities to an already-effective Form F-1, almost always on the same day the underlying offering prices. One record represents a single F-1MEF accession: a metadata.json header alongside the SGML-wrapped registration body and its non-graphic exhibits (typically a legality opinion, an auditor consent, and, since 2022, an EX-FILING FEES exhibit). The filer is the foreign-private-issuer registrant itself, together with any co-registrants from the parent F-1; underwriters and selling shareholders are not filers. The dataset spans March 1997 — when EDGAR began accepting Rule 462(b) filings under the Commission's 1996 simplification rulemaking — through the present, and is distributed as a ZIP archive of monthly YYYY/YYYY-MM.zip containers carrying HTML, TXT, and JSON files.
Programmatically retrieve the full list of dataset archive files, download URLs and dataset metadata.
Dataset Index JSON API
Download the entire dataset as a single archive file.
Download Entire Dataset:
Download a single container file (e.g. monthly archive) from the dataset.
Download Single Container:
The dataset captures every EDGAR submission filed on Form F-1MEF, the foreign-private-issuer counterpart of Form S-1MEF authorized by Rule 462(b) under the Securities Act of 1933. Each F-1MEF lets an issuer whose Form F-1 has already been declared effective expand that same offering by up to 20% of the maximum aggregate offering price set out in the prior F-1's Calculation of Registration Fee table, without preparing a new full registration statement. Because the prior F-1 is incorporated by reference in its entirety, the F-1MEF itself is intentionally minimal — a one-page legal mechanic. The form becomes effective automatically upon filing under Rule 462(b), which is why the effectiveness date and the date portion of the filing timestamp always coincide.
Records cover the entire EDGAR-era population of F-1MEF submissions, beginning in March 1997 — shortly after Rule 462(b) became operative — and continuing to the present. Because Form F-1MEF did not exist before Rule 462(b) and EDGAR was already the operative channel for registration statements by then, the dataset's coverage corresponds substantially to the full historical population of Form F-1MEF filings.
On disk, a record is a single accession-numbered folder named by the 18-digit dash-stripped accession number (for example 000095017025014884 for accession 0000950170-25-014884). The folder holds a metadata.json header alongside the SGML-wrapped HTML or plain-text documents that constitute the submission. Image files referenced by the filing — letterhead graphics, signature scans, embedded seals — are excluded from the dataset even when they appear in the EDGAR document manifest. Records are grouped into monthly ZIP containers organized as YYYY/YYYY-MM.zip, so each record sits inside the month folder corresponding to its filing date. File types found in the dataset are HTML (.htm/.html for modern filings), TXT (for early ASCII-only filings and occasional plain-text exhibits), and JSON (the per-record header).
A record is a small, predictable bundle. Every record contains:
metadata.json — a structured EDGAR header summarizing the submission, the registrant(s), and a manifest of every document.EX-FILING FEES, also known as Exhibit 107).Each persisted document on disk is the EDGAR SGML-wrapped form of the document, not raw HTML or raw text. The wrapper is a <DOCUMENT> envelope carrying <TYPE>, <SEQUENCE>, <FILENAME>, and <DESCRIPTION> tags followed by a <TEXT> block containing the actual HTML or ASCII payload. These four header tags mirror the corresponding entries in metadata.json → documentFormatFiles exactly, so consumers can join SGML headers to the JSON manifest on filename or sequence.
metadata.json headermetadata.json is a single JSON object that summarizes the EDGAR submission. The fields that carry intentional structured meaning are:
formType — always "F-1MEF" for this dataset.accessionNo — the dash-formatted accession number (e.g. "0000950170-25-014884").effectivenessDate — the date the registration becomes effective; under Rule 462(b) this equals the filing date.filedAt — full ISO-8601 timestamp with timezone offset (e.g. "2025-02-05T21:25:55-05:00").description — human-readable form description such as "Form F-1MEF - Registration statement to add securities to prior Form F-1 registration [Rule 462(b)]".linkToFilingDetails — canonical URL to the primary document on sec.gov/Archives/edgar/data/....linkToTxt — URL to the full .txt SGML submission file on EDGAR.linkToHtml — URL to the EDGAR filing-index page (...-index.htm).linkToXbrl — empty string. F-1MEF is not on the SEC's XBRL or inline-XBRL tagging list, so this field is consistently blank.documentFormatFiles — array of per-document manifest entries (see below).dataFiles — empty for this form type.entities — array of filers and co-registrants.seriesAndClassesContractsInformation — empty; not applicable to F-1MEF.documentFormatFilesEach manifest entry describes one document attached to the EDGAR submission and carries sequence (numeric string), size (string-typed bytes), documentUrl, description, and type. A representative manifest for a modern F-1MEF reads:
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[
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{"sequence": "1", "size": "108423", "documentUrl": ".../trinity_-_f-1mef_to_be_f.htm", "description": "F-1MEF", "type": "F-1MEF"},
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{"sequence": "2", "size": "48295", "documentUrl": ".../tbbb-ex5_01.htm", "description": "EX-5.01", "type": "EX-5.01"},
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{"sequence": "3", "size": "3673", "documentUrl": ".../tbbb-ex23_01.htm", "description": "EX-23.01", "type": "EX-23.01"},
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{"sequence": "4", "size": "67136", "documentUrl": ".../tbbb-exfiling_fees.htm", "description": "EX-FILING FEES", "type": "EX-FILING FEES"},
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{"sequence": "5", "size": "21247", "documentUrl": ".../img58595440_0.jpg", "description": "GRAPHIC", "type": "GRAPHIC"},
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{"sequence": " ", "size": "258054", "documentUrl": ".../0000950170-25-014884.txt", "description": "Complete submission text file", "type": " "}
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]
The trailing entry, with blank sequence and type, always points at the consolidated SGML submission text file. GRAPHIC entries reference images embedded in exhibits. Both the graphics and the standalone complete-submission .txt file are listed in the manifest but are not persisted on disk in the dataset; only the structured documents — the F-1MEF body and its non-graphic exhibits — are carried as files in the record folder. Consumers iterating the manifest should expect entries for which no local file exists.
entitiesThe entities array describes the filer(s) and any co-registrants. Each entry contains:
companyName — registrant name with an EDGAR role suffix appended (e.g. "BBB FOODS INC (Filer)").cik — Central Index Key as a numeric string.fileNo — the Securities Act file number assigned to this F-1MEF (distinct from, but cross-referenced to, the prior F-1's file number).filmNo — EDGAR film number.type — form code as filed by this entity (e.g. "F-1MEF").act — the Securities Act under which the filing is made (e.g. "33").sic — Standard Industrial Classification code with description (e.g. "5411 Retail-Grocery Stores").stateOfIncorporation — EDGAR jurisdiction code. Foreign codes such as "D8" (British Virgin Islands), "E9" (Cayman Islands), or "M2" (Bermuda) appear frequently because the form is restricted to foreign private issuers.fiscalYearEnd — MMDD string.irsNo — IRS Employer Identification Number; foreign issuers without a U.S. EIN typically report "000000000".tickers — array of trading symbols (e.g. ["TBBB"]).The primary document is the registration statement itself. It is intentionally short — typically a cover page, an explanatory note, and an exhibit index — because the substantive disclosure of the offering lives in the prior F-1 incorporated by reference. The structural fingerprint of an F-1MEF body is, in order:
"As filed with the U.S. Securities and Exchange Commission on [date].""FORM F-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933". (The MEF is filed on the F-1 cover form, not on a distinct F-1MEF cover.)"N/A" for foreign issuers without one), principal executive office address, and a U.S. agent for service of process (commonly Cogency Global, Corporation Service Company, or similar)."If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) ... ☒ [prior F-1 file number]". The prior file number (e.g. 333-284668) is filled in next to the checked box."THIS REGISTRATION STATEMENT SHALL BECOME EFFECTIVE UPON FILING WITH THE COMMISSION IN ACCORDANCE WITH RULE 462(b) UNDER THE SECURITIES ACT OF 1933, AS AMENDED."The body almost never contains a prospectus, financial statements, risk factors, business description, MD&A, or any of the other Items normally found in a stand-alone F-1. All such substantive content reaches the F-1MEF only by reference to the prior file number.
The exhibit set is small and predictable, reflecting the streamlined nature of Rule 462(b):
0.0001531), total offering amounts, and total fees due, plus a cross-reference to the prior registration's file number for any fee carry-forward.Every persisted .htm or .txt file in a record is the EDGAR SGML-wrapped form of the document, not the raw payload alone. The wrapper takes the shape:
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<DOCUMENT>
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<TYPE>EX-23.01
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<SEQUENCE>3
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<FILENAME>tbbb-ex23_01.htm
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<DESCRIPTION>EX-23.01
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<TEXT>
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<html> ... HTML payload ... </html>
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</TEXT>
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</DOCUMENT>
The <TYPE> value carries the EDGAR document-type code (F-1MEF, EX-5.01, EX-23.01, EX-FILING FEES, etc.); <SEQUENCE> is the 1-based filing sequence; <FILENAME> is the on-disk file name; <DESCRIPTION> is the human-readable label. Together these four tags duplicate the corresponding fields in the documentFormatFiles manifest, providing a redundant join point between SGML and JSON metadata that survives even minor JSON anomalies.
Two categories of content listed in the EDGAR manifest are intentionally not persisted in the dataset:
GRAPHIC entries with extensions such as .jpg, .gif, or .png — are listed in documentFormatFiles but are omitted from the record folder. Their manifest entries remain visible, but the underlying binaries are not included..txt file containing the full SGML submission with every document inline. This file appears as the trailing entry in documentFormatFiles (with blank sequence and type) and is exposed via linkToTxt, but the consolidated .txt is not persisted as a local file. The individual SGML-wrapped documents — which together carry the same content — are included instead.The prior Form F-1 referenced by file number is also not part of an F-1MEF record: it is incorporated only by reference, and consumers wishing to read the underlying offering documents must retrieve the prior F-1 separately by its file number (e.g. 333-284668).
The body of Form F-1MEF has been remarkably stable across the dataset window because the form's job — ticking the Rule 462(b) box, naming the prior file number, quantifying a top-up of no more than 20% of the prior maximum aggregate offering price, and incorporating the prior F-1 by reference — is essentially a one-page legal mechanic that has not been redesigned. The notable evolutions concern the exhibit set rather than the registration body:
EX-FILING FEES exhibit. F-1MEF records filed before the transition show the fee calculation inline on the cover; records filed after carry a separate EX-FILING FEES document with structured tables and explicit cross-references to the prior offering for fee carry-forward.EX-5.01 and EX-23.01 instead of EX-5 and EX-23), but the underlying document types — legality opinion and auditor consent — have remained the operative requirements throughout.Substantive disclosure obligations sit in the prior F-1, and changes to F-1 disclosure content over the past two decades (risk factors, MD&A, executive compensation, segment reporting, climate-related disclosures, and so on) flow into an F-1MEF only through the incorporation-by-reference mechanism, not through the F-1MEF's own pages.
The dataset spans roughly three EDGAR formatting eras, all represented in the file collection:
.txt file inside the SGML <DOCUMENT> wrapper, with the registration body laid out in fixed-width ASCII, signature blocks rendered as text, and exhibits appended as additional <DOCUMENT> blocks within the same submission..htm payloads inside the SGML envelope. Tables, fonts, and basic layout became expressible in markup, and signature graphics began appearing as separate GRAPHIC documents (now excluded from the dataset).EX-FILING FEES in 2022 added a structured, table-rich HTML exhibit alongside the cover.Across all eras the SGML <DOCUMENT> wrapper has been preserved on disk, providing a consistent join between the JSON manifest and the document payloads regardless of whether the inner payload is ASCII or HTML.
Several nuances matter for reading or extracting from a record:
333- file-number references back into the prior F-1 (and any pre-effective amendments to it). The F-1MEF itself only quantifies the size increase, names the prior file, and asserts the 20% cap.effectivenessDate and the date portion of filedAt always coincide; downstream pipelines should not look for a separate effectiveness order or notice of effectiveness.entities[].fileNo in metadata.json) and the prior F-1's file number (in the body of the registration statement, next to the Rule 462(b) checkbox and inside the explanatory note). Joining a record to its underlying offering requires the latter.documentFormatFiles lists every document in the EDGAR submission, including images and the complete .txt submission file, but the on-disk record contains only the structured non-graphic documents. The documentUrl for missing manifest entries still resolves on EDGAR, but no local file is produced.D8 for British Virgin Islands, E9 for Cayman Islands, M2 for Bermuda) populate stateOfIncorporation, and irsNo is frequently "000000000" for issuers without a U.S. EIN.metadata.json and the document set must be reconciled programmatically, the SGML <TYPE>, <SEQUENCE>, <FILENAME>, and <DESCRIPTION> headers inside each persisted file mirror the manifest exactly and provide a redundant identification path that survives even minor JSON anomalies.Each record is a Rule 462(b) abbreviated registration statement filed on EDGAR by a foreign private issuer that already has an effective Form F-1 covering an underwritten Securities Act offering. The filer is the issuer itself, together with any co-registrants (typically guarantors of registered debt) carried over from the original F-1. Underwriters, selling shareholders, and financial intermediaries are described in the offering documents but are not filers of the F-1MEF.
"Foreign private issuer" is defined in Rule 405 under the Securities Act. It means any issuer (other than a foreign government) incorporated or organized outside the United States, unless more than 50% of its outstanding voting securities are held of record by U.S. residents and any one of the following also applies: a majority of its executive officers or directors are U.S. citizens or residents, more than 50% of its assets are located in the U.S., or its business is principally administered in the U.S. An issuer that fails this test registers on Form S-1 and uses S-1MEF for any Rule 462(b) upsize.
F-1MEF filers are, in practice, foreign private issuers conducting an IPO or other Securities Act-registered offering on Form F-1, i.e., issuers that do not qualify (or do not elect) to use the short-form Form F-3. Seasoned F-3-eligible foreign private issuers use Form F-3MEF instead.
Rule 462(b) lets a registrant register additional securities of the same class for the same offering by filing an abbreviated registration statement that:
The 20% ceiling is measured on aggregate offering price, not share count. If the original F-1 registered USD 200 million, the F-1MEF can register up to USD 40 million more; the resulting share count depends on the actual pricing.
The operational trigger is bookbuilding demand or pricing that pushes the underwritten offering above the dollar amount registered on the F-1. Rule 462(b) requires that the F-1MEF be filed, and the fee paid (or drawn from the registrant's filing fee account), before the time of confirmation of sales of the additional securities. In practice that means same-day filing on or immediately adjacent to the pricing date.
Two features define this record type:
Filings are event-driven, not periodic, and occur only when a foreign-issuer F-1 offering needs to be upsized at pricing. Technical amendments occasionally appear as F-1MEF/A, typically to correct fee computations.
Rule 462(b) and the MEF family of forms were adopted in the Commission's 1996 simplification rulemaking (Securities Act Release No. 33-7411). F-1MEF became operative on EDGAR shortly thereafter, which is consistent with the dataset's earliest filings dating to March 1997. Because the form did not exist before Rule 462(b) and EDGAR was already the operative channel for registration statements by then, the dataset's coverage from 1997 onward corresponds substantially to the full historical population of Form F-1MEF filings.
Form F-1MEF occupies a narrow slot in the foreign private issuer registration regime: a Rule 462(b) abbreviated registration that adds capacity to an already-effective Form F-1. The most informative comparisons are with the parent F-1, its pre-effectiveness amendment F-1/A, the domestic Rule 462(b) counterpart S-1MEF, the seasoned-issuer cousin F-3MEF, the prospectus supplements (424B) that report actual pricing, the F-3/S-3 shelves that first-time foreign issuers cannot use, and the 6-K current reports that surround the same offering.
F-1 is the full long-form registration statement for foreign private issuers, carrying the complete prospectus, audited financials, risk factors, business description, MD&A, plan of distribution, and exhibits.
F-1MEF is a thin appendage to a specific effective F-1, incorporates the parent by reference, and registers up to 20% additional securities for the same offering. Substantive disclosure lives in the F-1; F-1MEF is meaningful only as a top-up. Use F-1 for content analysis (risk factors, financials, business); use F-1MEF to identify and size demand-driven upsizing.
Form F-1/A and F-1MEF differ on two binary axes: timing and cap.
An issuer enlarging an offering during bookbuilding files F-1/A; an issuer upsizing on pricing day because demand exceeded the original size files F-1MEF. A single offering can use both at different stages.
Form S-1MEF is structurally identical to F-1MEF — same Rule 462(b) basis, same 20% cap, same immediate effectiveness — but the filer population is binary: foreign private issuer (F-1MEF) versus U.S. domestic issuer (S-1MEF), paralleling the F-1/S-1 split at the parent level.
The two datasets are complementary for cross-market Rule 462(b) research but cannot be pooled, because the underlying disclosure regimes (foreign private issuer accommodations versus domestic reporting) differ at the parent-form level.
F-3MEF is the Rule 462(b) top-up for foreign issuers whose parent is an F-3 shelf registration — typically follow-ons, secondaries, or shelf takedowns. Same 20% cap, same immediate effectiveness.
The binary distinction is issuer seasoning: F-3MEF requires F-3 eligibility (public float and reporting history thresholds); F-1MEF is for issuers who could not yet use F-3 and registered the original offering on F-1. F-1MEF therefore captures IPO upsizing; F-3MEF captures follow-on or shelf-takedown upsizing.
The split is registration mechanism versus disclosure mechanism.
Both appear on or near pricing day for an upsized IPO and are easy to confuse, but they answer different questions. A complete picture of an upsized foreign IPO typically requires the F-1, the F-1MEF, and the 424B read together.
F-3 (foreign) and Form S-3 (domestic) are short-form shelf registrations restricted to seasoned issuers, supporting incorporation by reference of Exchange Act reports and delayed/continuous offerings.
They are not substitutes for F-1MEF: a first-time foreign issuer is categorically ineligible for F-3 at the IPO stage. The contrast explains why F-1MEF exists at all — without Rule 462(b), a foreign IPO issuer facing oversubscription on pricing day would have to file a new F-1 or an F-1/A and wait for effectiveness, which is incompatible with a one-day pricing window. F-1MEF fills the gap for issuers without shelf access.
Form 6-K is the foreign-issuer analogue of Form 8-K but operates under a furnishing rather than filing standard and follows home-country disclosure cadence rather than enumerated U.S. event triggers.
Relative to F-1MEF, the differences are categorical:
A 6-K may narrate the launch, pricing, or completion of an offering; F-1MEF handles only the U.S. registration top-up.
Four structural features jointly separate F-1MEF from every nearby dataset:
The filings are short and largely formulaic, with substantive disclosure inherited by reference from the parent F-1. This makes F-1MEF the right dataset for measuring Rule 462(b) usage by foreign IPO issuers, flagging demand-driven upsizing at pricing, and quantifying the prevalence of 20% top-ups in the foreign IPO population — and not a substitute for F-1 (substantive disclosure), F-1/A (pre-effectiveness changes), 424B (actual pricing and distribution), S-1MEF (domestic upsizing), or F-3MEF (seasoned-issuer upsizing).
The fields most roles return to are the registrant CIK and country in metadata.json, the prior F-1 file number cited in the explanatory note, the EX-FILING FEES exhibit (or pre-2022 cover-page fee table) showing incremental shares and aggregate offering price, the acceleration request, and the signature block identifying officers, directors, and the authorized U.S. representative.
Cross-border ECM origination teams build base rates on upsize behavior: ratio of F-1MEF increment to original F-1 amount, time from F-1 effectiveness to 462(b) acceptance, and frequency by sector and home jurisdiction (from metadata.json). Output: pitch material on how often bookrunners flex cross-border IPOs beyond the green shoe via 462(b), and how that capacity should be priced into base-deal sizing.
Securities counsel use the corpus as a precedent library on pricing day. They pull recent F-1MEFs to confirm explanatory-note wording referencing the prior file number, EX-FILING FEES exhibit structure under the post-2022 fee-table rules, acceleration-request phrasing, and signature-block formats for issuers from specific home jurisdictions (including the authorized U.S. representative line). The output is a working draft and checklist tied to current precedent.
Researchers studying underpricing and bookbuilding treat F-1MEF as a clean machine-identifiable signal that a cross-border IPO was upsized at pricing. They join F-1MEF to the parent F-1 via the prior file number, extract incremental share count and offering price from the fee exhibit, and merge with first-day trading data to test whether 462(b) upsizes predict aftermarket performance, underpricing, or long-run returns.
Quants ingest accession numbers, acceptance timestamps, and incremental notional to build a normalized cross-border IPO upsize event table from 1997 to present. The metadata fields supply CIK and point-in-time keys; the fee exhibit supplies incremental dollar amount. Derived features (upsize ratio, time-to-462(b), post-event drift) feed flipping, supply-overhang, and sector-rotation signals.
Compliance teams at underwriting banks, listing analysts at exchanges, and onboarding teams at custodians and transfer agents reconcile registered share counts against allotments, listing applications, and DTC eligibility. Because 462(b) lifts the registered count by up to 20% on the same day as effectiveness, the F-1MEF fee exhibit and prior file number are the keys downstream books-and-records must match, not the original F-1.
In-house counsel and finance leads at issuers preparing a U.S. listing review the dataset to scope the practical option value of Rule 462(b): frequency of F-1MEF use from their home jurisdiction, typical incremental size, fee burden, and acceleration handling. The fee exhibit and explanatory note drive decisions on whether to size the original F-1 conservatively and reserve 462(b) capacity, plus pricing-day readiness (board authorizations, signatory availability across time zones).
Private equity, M&A, and crossover diligence teams reviewing recently listed foreign issuers check whether an F-1MEF was filed alongside the F-1. Its presence signals strong pricing-day demand and a registered float materially above the F-1 cover-page figure. They use the incremental share count to recompute free float, lockup overhang, and post-IPO ownership.
Plaintiff- and defense-side litigation teams reviewing foreign-issuer IPOs that later underperformed or restated use the filing timestamp, acceleration request, incremental amount, and signature block as evidence of who authorized the upsize, when, and at what price. The full document set, including the explanatory note and signature pages, is the operative artifact.
Governance researchers study which officers signed the F-1MEF, whether the authorized U.S. representative line was used, and how board authorizations were referenced under time pressure. The signature block and any incorporated board-resolution language drive comparative analysis across home jurisdictions.
Teams building retrieval assistants for capital-markets and securities-law workflows index F-1MEF documents because they are short, self-contained, and tightly bound to one rule and one issuer category. The explanatory note, EX-FILING FEES exhibit, and prior file number serve as high-precision anchors for queries on 462(b) drafting, post-2022 fee-table format, acceleration language, and foreign-issuer signature handling.
The dataset's value lies in flagging cross-border IPO upsizing events and exposing the precise registration mechanics around them. The following workflows are representative.
Iterate every record's metadata.json to pull accessionNo, filedAt, registrant cik, tickers, sic, and stateOfIncorporation, then parse the EX-FILING FEES exhibit (or the cover-page Calculation of Registration Fee table for pre-2022 filings) for incremental share count, offering price per share, and aggregate offering price. Join to the prior F-1 by extracting the 333- file number from the explanatory note. Output: a panel keyed on accession number with upsize ratio, incremental notional, time-from-prior-effectiveness, and home-jurisdiction codes spanning 1997 to present, suitable for sector-rotation studies, IPO underpricing regressions, and supply-overhang signals.
Group records by sic, stateOfIncorporation, and filing year to compute frequency and median size of Rule 462(b) top-ups in each cross-border IPO sub-segment. Output: a slide showing, for example, the share of Cayman-incorporated software issuers that exercised 462(b), median upsize ratio, and median time from F-1 effectiveness to F-1MEF filing. Bankers feed this into base-deal sizing recommendations and into conversations with issuers about reserving 462(b) headroom.
Index the primary F-1MEF document and EX-5, EX-23, and EX-FILING FEES exhibits for keyword retrieval on stateOfIncorporation and counsel name. Securities counsel preparing a same-day filing pull the five most recent F-1MEFs from issuers in the same home jurisdiction (e.g. BVI, Cayman, Bermuda) and copy explanatory-note wording, the Rule 462(b) representation language, EX-FILING FEES table structure, and the U.S.-representative signature block as a starting draft. The SGML <TYPE> tags inside each persisted file identify exhibit class without parsing HTML.
For an issuer flagged by CIK, locate the F-1MEF record in the appropriate YYYY/YYYY-MM.zip, read the EX-FILING FEES table to capture the additional shares registered, and add them to the prior F-1's registered count to produce the post-462(b) total. Output: an updated registered-share figure used by exchange listing analysts to validate listing applications and by transfer agents and DTC onboarding teams to align books-and-records with the same-day effective registration.
For recently listed foreign issuers, check whether an F-1MEF accompanied the F-1 by querying the dataset on cik and the time window after F-1 effectiveness. When present, pull the incremental shares from the fee exhibit and recompute free float, insider/sponsor ownership percentages, and lockup overhang against the cover-page figure of the original F-1. Output: corrected ownership and float tables for crossover and PE diligence memos on issuers whose registered float diverged from the prospectus headline.
Build a retrieval index over the primary F-1MEF body, EX-5, EX-23, and EX-FILING FEES, using formType, stateOfIncorporation, effectivenessDate, and prior file number as filter facets. Because each filing is short, single-purpose, and pinned to one rule, the corpus serves as a high-precision answer source for assistant queries on Rule 462(b) drafting, the 20% cap representation, post-2022 fee-table format, foreign-issuer signature handling, and home-jurisdiction legality opinions.
Dataset Index JSON API: https://api.sec-api.io/datasets/form-f1mef-files.json
This endpoint returns the dataset metadata including name, description, last updated timestamp, earliest sample date, total records and total size, form types covered, container format, and file types. It also includes the download URL for the full dataset archive and the complete list of monthly container files with per-container metadata such as size, record count, updated timestamp, and individual download URL. Poll this endpoint to monitor which containers were modified in the most recent refresh and selectively download only the updated ones. No API key is required to access this endpoint.
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{
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"datasetId": "1f13365b-9ae0-69e2-902d-e74879e20fb3",
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"datasetDownloadUrl": "https://api.sec-api.io/datasets/form-f1mef-files.zip",
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"name": "Form F-1MEF Files Dataset",
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"updatedAt": "2026-04-22T03:02:30.234Z",
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"earliestSampleDate": "1997-03-01",
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"totalRecords": 1013,
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"totalSize": 3577922,
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"formTypes": ["F-1MEF"],
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"containerFormat": "ZIP",
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"fileTypes": ["TXT", "JSON", "HTML"],
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"containers": [
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{
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"downloadUrl": "https://api.sec-api.io/datasets/form-f1mef-files/2026/2026-04.zip",
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"key": "2026/2026-04.zip",
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"size": 142336,
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"records": 4,
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"updatedAt": "2026-04-22T03:02:30.234Z"
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}
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]
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}
Download Entire Dataset: https://api.sec-api.io/datasets/form-f1mef-files.zip?token=YOUR_API_KEY
Use this URL to download the complete dataset as a single ZIP archive containing all Form F-1MEF filings from March 1997 to present. This endpoint requires an API key.
Download Single Container: https://api.sec-api.io/datasets/form-f1mef-files/2026/2026-04.zip?token=YOUR_API_KEY
Use this URL pattern to download a single monthly container instead of the full dataset, which is useful for incremental updates or fetching a specific time range. Replace the year and month segments with the desired container key from the index. This endpoint requires an API key.
The dataset covers Form F-1MEF, the abbreviated Rule 462(b) registration statement filed by a foreign private issuer to register up to 20% of additional securities on top of an already-effective Form F-1. Each record is a single F-1MEF EDGAR submission, identified by accession number.
One record is a single accession-numbered F-1MEF submission, stored as a folder named by the 18-digit dash-stripped accession number. It contains a metadata.json header plus the SGML-wrapped primary F-1MEF document and its non-graphic exhibits — typically an EX-5 legality opinion, an EX-23 auditor consent, and (since 2022) an EX-FILING FEES exhibit.
Only foreign private issuers — as defined in Rule 405 under the Securities Act — file Form F-1MEF, and only when they already have an effective Form F-1 covering an underwritten Securities Act offering and need to register additional securities for the same offering. U.S. domestic issuers use S-1MEF instead, and F-3-eligible foreign private issuers use F-3MEF.
The filing is event-driven, triggered when bookbuilding demand or pricing pushes an underwritten offering above the dollar amount registered on the parent F-1. Rule 462(b) requires that the F-1MEF be filed and the fee paid before the time of confirmation of sales of the additional securities, and the registration becomes effective automatically upon filing without staff review or an order of effectiveness.
The dataset begins on 1997-03-01, shortly after Rule 462(b) and the MEF family of forms became operative under Securities Act Release No. 33-7411, and continues to the present. Because the form did not exist before Rule 462(b), this corresponds substantially to the full historical population of Form F-1MEF filings.
The dataset is distributed as ZIP containers organized as YYYY/YYYY-MM.zip (one archive per filing month). The files inside are HTML (.htm/.html) and TXT for the SGML-wrapped registration body and exhibits, and JSON for the per-record metadata.json header. Graphics and the consolidated EDGAR submission .txt file are intentionally excluded.
S-1MEF is the domestic counterpart and is structurally identical to F-1MEF; the choice between the two is governed solely by foreign-private-issuer status under Rule 405. F-3MEF is the Rule 462(b) top-up for seasoned foreign issuers whose parent registration is an F-3 shelf, so it captures follow-on and shelf-takedown upsizing, while F-1MEF concentrates on IPO upsizing by issuers that could not yet use Form F-3.