Short answer. Under Section 6 of RA 9048, the civil registrar posts the petition in a conspicuous place for ten consecutive days once he finds the petition and its supporting documents sufficient in form and substance. Only after that posting is completed does his period to decide the petition begin.
What the law says
He shall post the petition in a conspicuous place provided for that purpose for ten (10) consecutive days
RA 9048, Section 6 — Posting Decision And Transmittal. Read the full provision →
Ten consecutive days of posting
RA 9048 corrects clerical errors and certain first-name changes at the local civil registry rather than in court, and public posting is one of its safeguards. Section 6 requires that the registrar shall post the petition in a conspicuous place provided for that purpose for ten (10) consecutive days. The posting is meant to give notice to anyone who might be affected, so the correction is not made quietly behind closed doors. Ten consecutive days means the notice stays up without interruption, in a place where the public can actually see it, before the registrar moves to decide the petition on its merits.
Posting starts only after the papers pass review
The ten days do not begin the instant you file. The same section says the registrar posts the petition only after he finds the petition and its supporting documents sufficient in form and substance. In other words, he first examines your affidavit and the documents backing it; if they are complete and adequate, he then starts the ten-day posting. A deficient filing delays the whole timeline, because the posting clock waits for the registrar to be satisfied. Making sure your petition and its attachments are in order from the start is the practical way to avoid pushing the posting period back.
Posting for a change of first name adds publication
For an ordinary correction of a clerical error, the ten-day posting is the notice step. Where the petition seeks a change of first name or nickname, RA 9048 layers on an additional publication requirement handled under the section on the petition's form and contents — publication at least once a week for two consecutive weeks in a newspaper of general circulation. So the notice a petitioner must satisfy depends on what he is asking to change. Posting covers the standard clerical correction; a first-name change carries the extra publication burden on top of it before a decision is due.
Why the posting period matters to your timeline
Understanding the ten-day posting matters because the registrar's deadline to decide is measured from its completion, not from the day you filed. He must render a decision within five working days after the posting or publication requirement is completed. So the posting is both a public safeguard and the trigger that starts the decision clock. It does not, however, mean approval is automatic — a petition can still be denied if the documents do not support the correction, or if the change is actually a substantial one that belongs before a court rather than the administrative track under RA 9048.