TSC Ratings provides exclusive stock, ETF and mutual fund ratings and commentary based on award-winning, proprietary tools. Its "safety first" approach to investing aims to reduce risk while seeking solid outperformance on a total return basis.The following ratings changes were generated on Wednesday, May 20. We've upgraded Enzon Pharmaceuticals ( ENZN) from sell to hold. Strengths include the company's increase in net income and expanding profit margins. However, we also find weaknesses including a decline in the stock price during the past year, generally poor debt management and disappointing return on equity. Net income rose 307.6% compared with the same quarter last year, from $1.5 million to $6.2 million. Enzon's gross profit margin of 77.2% has increased from the year-ago quarter, but its 12.7% net profit margin trails the industry average. Revenue fell 0.3% since the year-ago quarter, though EPS increased. The debt-to-equity ratio or 5 is above the industry average, but the quick ratio of 4.6 implies an ability to cover short-term cash needs. Return on equity has decreased compared with the same quarter last year. We've upgraded Fluor ( FLR) from hold to buy, driven by its robust revenue growth, largely solid financial position with reasonable debt levels by most measures, notable return on equity, compelling growth in net income and impressive record of earnings per share growth. We feel these strengths outweigh the fact that the company shows weak operating cash flow. Revenue rose by 20.6% since the same quarter last year, and EPS are up, though we anticipate underperformance in the coming year relative to the company's two-year pattern of positive EPS growth. Fluor's debt-to-equity ratio of 0.1 is below the industry average, and its quick ratio of 1.1 implies an ability to avoid short-term cash problems. ROE has improved compared with the same quarter last year, and net income increased by 49.8%, from $136.7 million to $204.8 million.