# How to Track SEC Form 13F Filings: Regulatory Rules, Deadlines, and Analytical Limits
1. Statutory Framework and Filing Thresholds
SEC Form 13F is a mandatory quarterly disclosure report required pursuant to Section 13(f) of the Securities Exchange Act of 1934 and SEC Rule 13f-1.Monthly Threshold Testing
Under Rule 13f-1, an institutional investment manager determines its filing obligation by testing whether the aggregate fair market value of its Section 13(f) securities reaches or exceeds $100 million on the last trading day of any month of a calendar year. If the threshold is met, the manager generally must file its initial Form 13F for the fourth quarter (ending December 31) of that year, followed by mandatory quarterly filings for the subsequent calendar year.
2. 45-Day Statutory Filing Schedule and Calendar Shifts
Form 13F is due within 45 calendar days following the end of each calendar quarter. Under SEC Rule 0-3, if a deadline falls on a weekend or federal holiday, the filing deadline shifts to the immediate next business day.
2026/2027 Filing Schedule (Adjusted for Business Days):
- Q1 2026 (Period Ending March 31, 2026): Due May 15, 2026
- Q2 2026 (Period Ending June 30, 2026): Due August 14, 2026
- Q3 2026 (Period Ending September 30, 2026): Due November 16, 2026 (shifted from Saturday Nov 14 / Sunday Nov 15)
- Q4 2026 (Period Ending December 31, 2026): Due February 16, 2027 (shifted from Sunday Feb 14 / Presidents' Day holiday Feb 15)
3. Scope of Reported Securities & Key Exclusions
- Covered Securities: Only securities explicitly included on the SEC's quarterly Official List of Section 13(f) Securities (primarily exchange-traded equities, equity options, and convertible bonds).
- Omitted Positions: Short positions are not reported on Form 13F. Cash, commodities, unlisted foreign securities, and synthetic derivatives are likewise excluded.
4. Analytical Best Practices
- Account for the 45-Day Lag: Positions reflect holdings on the final day of the prior quarter, not real-time intraday portfolios.
- Evaluate Relative Sizing: Assess position changes as a percentage of total reported 13F assets to gauge true portfolio conviction.