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 _______

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 _______ No___X____

Marlim Field Special Participation

(Rio de Janeiro, July 23, 2007). – PETRÓLEO BRASILEIRO S/A - PETROBRAS, [Bovespa: PETR3/PETR4, NYSE: PBR/PBRA, Latibex: XPBR/XPBRA, BCBA: APBR/APBRA], a Brazilian international energy company, announces that in view of the news the press has divulged regarding an alleged calculation error the Company may have made in paying the so-called “Special Participation” governmental contribution – which incurs on oil production, and in this specific case in connection with the Marlim Field, in the Campos Basin –, we hereby clarify that Petrobras has always acted in strict observance of the law and of the National Petroleum Agency’s (ANP) regulations and that it indeed paid the exact amount of the special participation charged by the ANP, under the terms of the deliberation of that agency’s highest decision-making body, its COLLEGIAL BOARD.

The ANP recently changed its collection values by revoking decisions made by its own board. The ANP is billing Petrobras again, retroactively and for a higher sum, for ascertainment periods Petrobras has already paid in compliance with the ANP’s own previous decision.

Petrobras, as an ANP concessionaire for oil exploration and production activities, will respect the ANP’s decisions and deliberations at all times, as long as they observe the legal order in effect in Brazil.

It is our understanding, however, that there is no legal basis for ANP’s decision reversal regarding ascertainment periods that have already been paid, as this violates constitutional principles and causes this Company to seek to protect its rights in order to maintain its good corporate management practices and to defend its shareholders’ interests.

This document may contain forecasts that merely reflect the expectations of the Company’s management. Such terms as “anticipate”, “believe”, “expect”, “forecast”, “intend”, “plan”, “project”, “seek”, “should”, along with similar or analogous expressions, are used to identify such forecasts. These predictions evidently involve risks and uncertainties, whether foreseen or not by the Company. Therefore, the future results of operations may differ from current expectations, and readers must not base their expectations exclusively on the information presented herein.

This press release may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management's current view and estimates offuture 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.