SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16 of the

Securities Exchange Act of 1934

For the month of December 2014

Commission File Number 1-13758

PORTUGAL TELECOM, SGPS, S.A.

(Exact name of registrant as specified in its charter)

Av. Fontes Pereira de Melo, 40
1069 - 300 Lisboa, Portugal

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F  x  Form 40-F  o

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  o  No  x

Announcement  |  Lisbon  |  8 December 2014

Material fact disclosed by Oi

Portugal Telecom, SGPS S.A. hereby informs on the material fact disclosed by Oi, S.A., regarding the Oi S.A. Board of Directors Approval of the Sale of Shares of PT Portugal to Altice S.A., according to the company’s announcement attached hereto.

www.ptsgps.pt

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Oi S.A.

Corporate Taxpayers’ Registry (CNPJ/MF) No. 76.535.764/0001-43

Board of Trade (NIRE) No. 33.3.0029520-8

Publicly-Held Company

MATERIAL FACT

Oi S.A. Board of Directors Approval of the Sale of Shares of PT Portugal to Altice S.A.

Oi S.A. (“Oi” or the “Company”, Bovespa: OIBR3, OIBR4; NYSE: OIBR and OIBR.C), in accordance with article 157, paragraph 4 of Law No. 6,404/76 (the “Brazilian Corporation Law”) and the Brazilian Securities and Exchange Commission (Comissão de Valores Mobiliários - CVM) Instruction No. 358/02, continuing with the Material Facts dated November 3, 2014 and November 30, 2014, informs its shareholders and the market in general that, on this date, the Board of Directors of Oi finalized the formalities to approve the general terms and conditions for the sale of all of the shares of PT Portugal SPGS S.A. (“PT Portugal”) to Altice Portugal S.A. (“Altice PT”), a wholly-owned subsidiary of Altice S.A. (and together with Altice PT, “Altice”).  The sale substantially involves PT Portugal’s operations in Portugal and Hungary.  The effectiveness of the purchase and sale contract will depend on the approval by the shareholders of Portugal Telecom SGPS, S.A. (“PT SGPS”), which will be called in due course.

With this approval, Oi will transfer to Altice all of the shares issued by PT Portugal for an enterprise value of 7.4 billion Euros, adjusting for cash and debt and including an earn-out of 500 million Euros related to PT Portugal’s generation of future revenue.  The price to be paid by Altice will suffer adjustments usually adopted in similar transactions, in accordance with PT Portugal’s cash holdings on the closing of this transaction.

Prior to the consummation of the sale and as a condition precedent to its closing, certain corporate reorganizations will be required to take place in order to delineate the operations to be transferred as well as to separate PT Portugal’s investments which will not be included in the sale, including the investments in Africatel GmbH & Co. KG and Timor Telecom S.A. and the investments held by PT Portugal in Rio Forte Investments S.A. (which are subject of the share exchange agreement with PT SGPS under which this investment will be exchanged for shares issued by Oi, which is still subject to approval by the CVM), as well as all or part of PT Portugal’s indebtedness.

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In addition to the corporate reorganization considered above, the closing of this sale will be conditioned on, among other matters, obtaining the required regulatory and antitrust approvals, in accordance with applicable law.

With this step concluded, Oi continues its objective of reinforcing its financial capacity in order to maintain its objective of leading the consolidation movement in the Brazilian telecommunications market.

Oi will maintain its shareholders and the market informed of any material events related to this subject.

Rio de Janeiro, December 8, 2014.

Oi S.A.

Bayard De Paoli Gontijo

Chief Executive Officer, Chief Financial Officer and Investor Relations Officer

Special Note Regarding Forward-Looking Statements:

This communication may contain forward-looking statements. Statements that are not historical facts, including statements regarding the beliefs and expectations, business strategies, future synergies and cost savings, future costs and future liquidity, are forward-looking statements. The words “will,” “will be,” “should,” “could,” “may,” “should be,” “could be,” “may be,” “estimates,” “has as an objective,” “targets,” “target “goal,” “anticipates,” “believes,” “expects,” “forecasts,” “intends,” “plans,” “predicts,” “foretells,” “projects,” “points to” and similar expressions are intended to identify forward-looking statements and are subject to a number of risks and uncertainties. These statements reflect current expectations. In light of the many risks and uncertainties surrounding the offer, you should understand that we cannot assure you that the forward-looking statements contained in this communication will be realized. Undue reliance should not be placed on such statements.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: December 8, 2014

FORWARD-LOOKING STATEMENTS

This document may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management’s current view and estimates of future economic circumstances, industry conditions, company performance and financial results. The words “anticipates”, “believes”, “estimates”, “expects”, “plans” and similar expressions, as they relate to the company, are intended to identify forward-looking statements. Statements regarding the declaration or payment of dividends, the implementation of principal operating and financing strategies and capital expenditure plans, the direction of future operations and the factors or trends affecting financial condition, liquidity or results of operations are examples of forward-looking statements. Such statements reflect the current views of management and are subject to a number of risks and uncertainties. There is no guarantee that the expected events, trends or results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations.

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