[2] Safety-Kleen was started in the late 1950s and early 1960s when Ben Palmer invented the parts washer which he decided to lease to customers and service by removing and replenishing the solvent in the machines.

In 1968, the Safety-Kleen business was acquired by Chicago Rawhide, and under the leadership of Don Brinckman Safety-Kleen became a publicly traded company and enjoyed tremendous growth and business success over 30 years, eventually joining the Fortune 500.

[3] In 1998, Safety-Kleen fell victim to a hostile takeover by Laidlaw Environmental.

[4] In this period, the company hid the failure of the merger[5] and in 2002, civil and criminal charges were filed by the SEC and the United States Attorney's Office against Safety-Kleen and four of its former senior executives for "perpetrating a massive accounting fraud from at least November 1998 through March 2000.

[7] The company successfully emerged from bankruptcy[4] and refinanced its senior debt in 2005.