The U.S.-listed shares of Brazil-based Petroleo Brasileiro S.A. /zigman2/quotes/200745132/composite PBR -5.46% , also known as Petrobras, fell 0.5% on NYSE-leading volume in afternoon trading Wednesday, to buck a broad rally in the energy sector, after the oil and gas exploration company priced a secondary share offering at a discount. Trading volume was 48.1 million shares, compared with the full-day average of about 13.5 million shares. Petrobras disclosed Wednesday that its public offering of 69.3 million American Depositary Shares (ADS) priced at $15.84 each, or 0.9% below Tuesday's closing price of $15.98. The offering was valued at $1.10 billion, which represented about 1.1% of the company's market capitalization. The stock lost 3.0% over the past three months, while the SPDR Energy Select Sector ETF /zigman2/quotes/206420077/composite XLE -3.89% has slipped 4.1% and the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.72% has gained 3.6%.