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 January 2015

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  |  30 January 2015

Material fact disclosed by Oi

Portugal Telecom, SGPS S.A. hereby informs on the material fact disclosed by Oi, S.A. related to the cancellation of the shareholder compensation policy, according to the company’s announcements 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. 33.300.29520-8

Publicly-Held Company

MATERIAL FACT

Cancellation of the Shareholder Compensation Policy

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 and the Brazilian Securities and Exchange Commission (Comissão de Valores Mobiliários — CVM) Instruction No. 358/02, informs its shareholders and the market that the Board of Directors has approved the cancellation of the Shareholder Compensation policy for the fiscal years 2013-2016, that was previously disclosed in the Material Fact dated August 13, 2013, therefore remaining subject only to the provisions of Law No. 6,404/76 and the Company’s by-laws.

Rio de Janeiro, January 29, 2015.

Oi S.A.

Bayard De Paoli Gontijo

Chief Executive Officer,

Chief Financial Officer and Investor Relations Officer

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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: January 30, 2015

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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