Nationality consolidation — 10-year bona-fide protection (Art 12-B)

Art 12-B of Lei 37/81 is a protection-of-bona-fide-third-parties mechanism, not an acquisition pathway. It does not confer nationality on anyone. Rather, it bars the cancellation (anulação) of a fraudulently-obtained naturalisation once ten years have elapsed from the date of acquisition and where bona-fide third parties have derived nationality rights from the fraudulent acquirer.

The practical effect is a ten-year limitation on the State's power to unwind fraud-based naturalisations where innocents would be prejudiced. The fraudulent acquirer themselves is NOT protected — only their bona-fide third-party derivative nationals.

LO 1/2026 doubled the prior 6-year period (introduced by LO 2/2018) to 10 years, effective 2026-05-19. TC Acórdão 1133/2025 (Proc. 1383/2025, 15-12-2025, DR Série I n.º 2, 05-01-2026) struck the proposed Art 12-B n.3 "manifestly fraudulent" (manifesta fraude) clause from Decreto AR 17/XVII before it became law; LO 1/2026 was enacted without that clause.

** note (PT-VC-011 — over-correction exemplar):** The current rule is 10 years. Do NOT revert to 6 years. The 6-year rule was correct only for the W5-W6 era (LO 2/2018, EIF 06-07-2018 — 2026-05-18); that version is documented as PT-NAT-12B-CONSOL-W5 (superseded).

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This is a protection-not-an-acquisition mechanism. The following conditions must be met for the 10-year bar to operate:

1. Original acquisition by fraud: The base naturalisation was obtained through misrepresentation or fraud by the acquirer. This is established in cancellation proceedings.
2. 10 years elapsed: At least 10 years have passed between the date the fraudulent naturalisation was registered (Art 12 effects date) and the initiation of cancellation proceedings.
3. Bona-fide third-party derivative nationals exist: Third parties who derived their Portuguese nationality from the fraudulent acquirer (e.g., children born after the naturalisation) must exist and have acquired that status in good faith, without knowledge of the fraud.
4. Cancellation would prejudice the derivative nationals' status: If cancellation of the fraudulent acquirer's naturalisation would extinguish the nationality of bona-fide derivatives, Art 12-B operates as a bar.

The bona-fide derivative nationals themselves need not have done anything; the protection is structural (a bar in law).

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Art 12-B is a procedural defence in cancellation proceedings, not an application. There is no application process for the "route." The protection arises automatically by operation of law once its conditions are met.

In practice, bona-fide third-party derivatives whose status is challenged in cancellation proceedings assert Art 12-B in administrative or judicial appeal proceedings before the IRN/CRC (administrative level) and the administrative courts / STA (judicial level).

Evidence relevant to Art 12-B proceedings:

• Proof of the date of registration of the original naturalisation (Art 12 certificate or RNI record)
• Proof that 10 years have elapsed
• Proof of derivative acquisition in good faith (e.g., birth certificate, evidence of unawareness of any fraud)
• Any court or administrative findings on the nature of the fraud

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Art 12-B operates within cancellation proceedings, not as a standalone application process:

1. Cancellation proceedings initiated: IRN/CRC, the Ministério Público, or a competent authority identifies a potentially fraudulent naturalisation and initiates cancellation at the administrative or judicial level.
2. 10-year check: If 10 or more years have elapsed since the fraudulent registration, the Art 12-B bar is assessed.
3. Third-party derivative identification: The proceedings assess whether bona-fide derivative nationals exist and whether cancellation would prejudice them.
4. Bar application: If the conditions are met, cancellation is barred as to the derivative nationals. The fraudulent acquirer's naturalisation may still be cancelled in a separate proceeding or the same proceeding with severed effect.
5. Judicial review: Administrative courts and the STA have jurisdiction over nationality cancellation decisions. Pre-LO 2/2006 era cases went to civil courts/STJ; post-2006 to administrative courts/STA.

Authorities: IRN/CRC; Ministério Público; administrative courts; Supremo Tribunal Administrativo (STA).

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The provision operates as a procedural shield in cancellation proceedings. Key structural elements:

1. Precondition: The original naturalisation must have been obtained by fraud/misrepresentation (acquisition through ordinary error or administrative mistake is a distinct question).
2. Time bar: 10 years from the date of acquisition (date of registration under Art 12 Lei 37/81 — not from discovery of the fraud).
3. Protected parties: Only bona-fide THIRD PARTIES who derived nationality rights. The fraudulent acquirer is never protected by Art 12-B; their own nationality remains cancellable at any time under general administrative-law principles.
4. TC-struck clause: The "manifestly fraudulent" carve-out (Art 12-B n.3, which would have removed the protection even after 10 years if the fraud was "manifest") was struck by TC Ac. 1133/2025 and does not appear in LO 1/2026.
5. Effect: If the 10-year bar applies, the cancellation is barred to the extent it would extinguish the derivative nationals' status. The fraudulent acquirer's own nationality may still be cancelled.

Contextual background: Art 12-B was first introduced by LO 2/2018 with a 6-year threshold (W5). The Sephardic naturalisation programme generated a large volume of applications and some fraud investigations, providing the practical context for Art 12-B's importance. LO 1/2026 doubled the threshold to 10 years in part to extend the protection period for families who relied in good faith on a parent's naturalisation. The TCA Sul Acórdão Proc. 2854/11.6BELSB (02-09-2023) applied the 6-year Art 12-B version in a decolonisation-era historical case, confirming that Art 12-B is operative in court practice.

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