The Firm represented First Reserve, in connection with the sale of IRISNDT. Financial terms of the transaction were not disclosed.~~IRISNDT is a privately-owned NDT, Inspection, and Integrity Engineering company with operations in the United States, Canada, the United Kingdom, and Australia. The company serves a blue-chip customer base in a wide range of end-markets including critical processing infrastructure, general industrial applications, renewables, LNG, and biofuels around ongoing operational activities and maintenance turnaround projects.~~First Reserve is a leading global private equity firm investing across diversified energy, utility, and industrial end-markets. Founded in 1983, First Reserve has more than 40 years of industry insight and has cultivated a differentiated network of global relationships. The firm has raised over $34 billion of aggregate capital and has developed operational expertise built from over 750 transactions, including platform investments and add-on acquisitions.~~The Simpson Thacher team included Michael T. Holick and Arie van Wijngaarden (M&A); and Larry Moss and Alisa Tschorke (Employee Benefits and Executive Compensation).