Shares of Schlumberger NV (NYSE:SLB) are trading higher after oil surpassed $90 per barrel. The rise is also attributed to OPEC maintaining its growth forecasts and predicting a supply shortfall. This could lead to increased drilling and exploration activities, boosting demand for Schlumberger's services and potentially increasing the company's revenues and profitability. Saudi Arabia's extension of production cuts and a projected sharp drop in world oil inventories also contribute to the bullish sentiment.