OI S.A.
Corporate Taxpayer's ID (CNPJ/MF): 76.535.764/0001-43
Company Registry (NIRE): 33.300.29520-8
Publicly-Held Company

NOTICE TO THE MARKET
2014 Annual Sustainability Report

Oi S.A. disclosed today its 2014 Annual Sustainability Report, which was prepared in accordance with the Global Reporting Initiative (GRI) guidelines for the fourth year.

Committed to the reporting development, Oi adopted t his year the GRI's G4 version, enhancing its materiality process and focusing on the most material issues to its stakeholders. The analysis of these issues was the base to select the indicators.

Another innovation was the preparation of the abbreviated version of the report, in Portuguese and English versions, which aims to objectively present to the stakeholders the social, economic and environmental highlights of 2014.

To access the 2014 Sustainability Report, visit Oi S.A.'s IR website at www.oi.com.br/ir.

Rio de Janeiro, May 29, 2014.

Oi S.A.
Flavio Nicolay Guimaraes
Chief Financial Officer and Investor Relations Officer

To see the PDF version, click here.

(¹) This translation is still subject to the auditors review

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