Discovering an error in a previously filed Form 13F creates an immediate compliance obligation: you must file an amendment. The SEC's guidance is unambiguous — if you identify a material inaccuracy in a prior filing, you are required to correct it promptly. There is no grace period, and no waiting until the next quarterly filing cycle to fold the correction in.
The Two Types of 13F Amendments
Form 13F amendments come in two forms, and the distinction matters. A restatement replaces your entire prior filing with a corrected version. An additive amendment adds new holdings entries that were missing from the original filing but does not replace it wholesale. The EDGAR submission type for both is 13F-HR/A. The cover page must indicate the amendment number (Amendment No. 1, No. 2, etc.) and which type it is. Choosing the wrong type is itself an error that would require another amendment to correct.
What Changed in 2023
Starting January 3, 2023, all Form 13F filings — including amendments to reports for any prior quarter — must use the updated Form 13F format. This means that even if you are amending a report for a quarter that ended in 2021, the amendment must be built using the 2023 form requirements. The most significant practical change: market values must now be rounded to the nearest dollar, not the nearest thousand dollars. If you are amending an older filing, your amended values must use dollar-level rounding even if the original used thousand-dollar rounding.
The Most Common Reasons to Amend
The errors that most frequently require 13F amendments are CUSIP errors (wrong CUSIP, leading zeros stripped by Excel, scientific notation corruption), market value errors (non-round values, values pulled from the wrong date), issuer name mismatches against the official SEC 13F securities list, and missing positions omitted from the original filing. Each of these is also among the most common initial filing errors — which is why thorough pre-submission validation matters.
Confidential Treatment and Amendments
If you are amending a filing that originally included a confidential treatment request, the amendment's confidential treatment component must also be filed electronically via EDGAR. Since February 28, 2023, paper confidential treatment requests are no longer accepted, regardless of the original filing date.
File Before the SEC Finds the Error
Firms that proactively amend when they discover errors are consistently treated more favorably in enforcement proceedings than firms whose errors are flagged externally. If you've identified an error in a prior Form 13F and need help building and submitting the amendment, contact File13F. We handle amendments as well as initial filings and can turn around corrected XML quickly.