Prospectus Supplements (424B): Parse Offering Terms from SEC Filings

Overview

424B filings are prospectus supplements that companies file when they sell securities off a shelf registration (S-3/F-3). They contain the final deal terms: price, shares, proceeds, underwriting fees, and dilution impact. EdgarTools parses all 424B variants into a Prospectus424B object, with a Deal property that normalizes everything into clean numeric values.

Form	Typical Use
424B2	Structured notes, debt (large banks)
424B3	Resale prospectuses (PIPE resales)
424B4	Final priced prospectuses (IPOs)
424B5	Shelf takedowns (ATM, firm commitment, PIPE)

Quick Start

from edgar import Company

company = Company("ALZN")
filing = company.get_filings(form="424B5")[0]
prospectus = filing.obj()          # Prospectus424B
deal = prospectus.deal             # Deal: normalized summary

deal.price                         # 2.48
deal.shares                        # 1_500_000
deal.gross_proceeds                # 3_720_000.0
deal.lead_bookrunner               # "H.C. Wainwright & Co."

The Deal Object

Access via prospectus.deal. Always returns a Deal object (never None). Individual properties return None when data is unavailable.

Core Deal Terms

Property	Type	Description
`price`	`float \\| None`	Per-unit offering price
`shares`	`int \\| None`	Number of shares offered
`gross_proceeds`	`float \\| None`	Total offering amount (before fees)
`net_proceeds`	`float \\| None`	Proceeds after underwriting fees
`security_type`	`str \\| None`	Security description ("Common Stock", "Senior Notes")
`offering_type`	`OfferingType`	Enum: `FIRM_COMMITMENT`, `ATM`, `BEST_EFFORTS`, etc.
`is_atm`	`bool`	Whether this is an at-the-market offering

Underwriting Economics

Property	Type	Description
`fee_per_share`	`float \\| None`	Per-unit underwriting discount
`total_fees`	`float \\| None`	Total underwriting fees
`discount_rate`	`float \\| None`	Fee as fraction of price (0.05 = 5%)
`fee_type`	`str \\| None`	`"underwriting_discount"` or `"placement_agent_fees"`
`lead_bookrunner`	`str \\| None`	Lead underwriter or placement agent
`underwriter_count`	`int`	Number of underwriters in syndicate

Dilution (Equity Offerings Only)

Property	Type	Description
`dilution_per_share`	`float \\| None`	Dilution to new investors
`dilution_pct`	`float \\| None`	Dilution as percentage
`shares_before`	`int \\| None`	Shares outstanding before offering
`shares_after`	`int \\| None`	Shares outstanding after offering
`ntbv_before`	`float \\| None`	Net tangible book value per share before
`ntbv_after`	`float \\| None`	Net tangible book value per share after

Serialization

deal.to_dict()        # Flat dict of all non-None values (good for DataFrames)
deal.to_context()     # Markdown-KV text for LLM prompts

Offering Classification

The offering_type property classifies the deal:

Value	Description	Price/Shares Available?
`FIRM_COMMITMENT`	Bank buys all shares, resells	Yes
`ATM`	At-the-market (sold gradually)	Usually no (market price)
`BEST_EFFORTS`	Agent sells on best-efforts basis	Yes
`PIPE_RESALE`	Resale of privately placed shares	Varies
`STRUCTURED_NOTE`	Bank-issued structured product	Different meaning
`DEBT_OFFERING`	Corporate bonds / notes	Usually percentage

if deal.is_atm:
    # Price and shares are typically None for ATM offerings
    print(f"ATM program: up to ${deal.gross_proceeds:,.0f}")
else:
    print(f"{deal.shares:,} shares @ ${deal.price:.2f}")

Prospectus Sub-Objects

The Prospectus424B exposes the raw extracted data that the Deal synthesizes:

prospectus.cover_page          # CoverPageData: company, registration, flags
prospectus.pricing             # PricingData: per-unit and total columns
prospectus.underwriting        # UnderwritingInfo: syndicate, fee type
prospectus.offering_terms      # OfferingTerms: shares, warrants, use of proceeds
prospectus.selling_stockholders  # SellingStockholdersData: PIPE resale tables
prospectus.dilution            # DilutionData: NTBV impact table
prospectus.capitalization      # CapitalizationData: actual vs. as-adjusted
prospectus.structured_note_terms  # StructuredNoteTerms: CUSIP, maturity (424B2)
prospectus.filing_fees         # FilingFeesData: from XBRL exhibit

Selling Stockholders (PIPE Resale Filings)

For PIPE resale prospectuses (typically 424B3), the selling stockholders table lists investors reselling privately placed shares:

ss = prospectus.selling_stockholders   # SellingStockholdersData or None
if ss:
    ss.count                           # Number of selling stockholders
    for entry in ss.stockholders:
        entry.name                     # "Lincoln Park Capital Fund, LLC"
        entry.shares                   # 1500000 (parsed int, None on failure)
        entry.shares_before            # 2000000
        entry.shares_after             # 500000
        entry.pct_before               # 9.5 (parsed float)
        entry.pct_after                # 2.8
        entry.warrants                 # 750000 (warrants/convertibles, if present)

Raw string values are always preserved (shares_offered, shares_before_offering, etc.). The numeric properties (shares, shares_before, etc.) parse them to int/float, returning None on failure.

DataFrame Output

df = ss.to_dataframe()
# Returns DataFrame with numeric columns:
#   name | shares_before | pct_before | shares_offered | shares_after | pct_after | warrants

Offering Type Check

if prospectus.offering_type.has_selling_stockholders:
    # This is a PIPE_RESALE or BASE_PROSPECTUS_UPDATE
    ss = prospectus.selling_stockholders

Shelf Lifecycle

Track where a prospectus sits in its shelf registration lifecycle:

lc = prospectus.lifecycle          # ShelfLifecycle
lc.takedown_number                 # 3 (this is the 3rd offering)
lc.total_takedowns                 # 5
lc.shelf_expires                   # date(2027, 8, 2)
lc.avg_days_between_takedowns      # 180.0
lc.shelf_registration              # Filing object for the S-3

To navigate the other direction -- from the S-3 shelf forward to its 424B takedowns -- use the RegistrationS3 data object. filing.obj() returns it automatically for S-3, S-3/A, S-3ASR, S-3D, and S-3DPOS filings.

from edgar import Company

company = Company("ALZN")
s3_filing = company.get_filings(form="S-3")[0]
s3 = s3_filing.obj()                   # RegistrationS3

s3.total_offering                      # total registered amount in dollars
s3.takedowns                           # Filings with all 424B forms from this shelf
s3.offering_type.display_name          # "Resale Registration"

See the S-3 Registration Statement guide for the full API.

Working with Multiple Offerings

Build a DataFrame of a company's offering history:

import pandas as pd
from edgar import Company

company = Company("ALZN")
filings = company.get_filings(form="424B5")

rows = []
for filing in filings:
    prospectus = filing.obj()
    d = prospectus.deal.to_dict()
    d['filing_date'] = str(filing.filing_date)
    rows.append(d)

df = pd.DataFrame(rows)

Rich Display

Both Prospectus424B and Deal render as Rich panels in terminals and notebooks:

prospectus          # Shows cover page, pricing table, underwriting
prospectus.deal     # Compact deal summary panel