The SEC’s May 5, 2026 proposal to permit optional semiannual reporting on a new Form 10-S, rather than mandating quarterly Form 10-Q filings, represents the dominant catalyst anchoring the 55% market-implied probability that the agency will not eliminate the quarterly requirement. Under the draft amendments to Exchange Act Rules 13a-13 and 15d-13, companies could elect the lighter regime annually via a check-box on Form 10-K, while quarterly reporting remains the default and full annual 10-K obligations continue unchanged. A 60-day public comment period is now underway, with adoption uncertain given potential investor pushback over reduced interim transparency and the historical emphasis on frequent disclosure to support efficient capital allocation. Traders appear to price the proposal as a modest burden-reduction measure rather than a wholesale removal of the 55-year-old quarterly framework, especially as smaller issuers may still favor quarterly cadence for signaling purposes.