v5.31.1

Fixed

• Schedule 13D/13G silently dropped CUSIPs with the new <issuerCusips> wrapper — SEC began wrapping <issuerCusipNumber> inside an <issuerCusips> container element on some Schedule 13D/13G filings (e.g. CIK 1906837 13D, CIK 1425851 13G). The parser's BS4 recursive=False lookup at the top-level only matched the flat layout, so subject_company.cusip came back as '' whenever the wrapper was present. Parsing now falls back to a recursive lookup when the flat probe misses, handling both wire formats. (#802, PR #803 by @HristoRaykov)

• Schedule 13D/13G event-date attribute name mismatch — Schedule13D exposed the triggering-event date as date_of_event while Schedule13G exposed it as event_date, breaking duck-typing across a mixed list of 13D/13G filings and forcing callers to use getattr / hasattr. Both classes now accept either name; the underlying attribute is unchanged, so existing code keeps working. (#804, PR #805 by @0ywfe)

• Spurious DocumentTooLargeError from StreamingParser on legitimate documents — The streaming HTML parser accumulated len(etree.tostring(elem)) on every lxml iterparse end event. Because tostring serializes the full subtree and end fires for every closing tag, nested elements were counted multiple times — large nested HTML could trip max_document_size even though the source document was under the limit. The per-event accumulator is also redundant: HTMLParser._parse already validates len(html.encode("utf-8")) against max_document_size before invoking streaming mode. The accumulator and its state are removed; size is now checked once at the top of StreamingParser.parse() and the same encoded bytes are reused for iterparse. (#806 by @kevinchiu)

Full Changelog: v5.31.0...v5.31.1