The company was bought by Thermo Fisher Scientific in 2015,[2] having previously existed as part of the Johnson Matthey Fine Chemicals & Catalysts Division.

[4][5] Alfa Aesar was formed from a series of company mergers: Both Lancaster Synthesis and Avocado had close trading links to Alfa at various times prior to the takeover: the organic products sold in Germany through the Alfa-Ventron catalogue were sourced from Lancaster, while Avocado products were distributed both in the US and Germany by the combined Alfa-Aesar.

On June 25, 2015, Johnson Matthey agreed to sell Alfa Aesar for an amount of £256 million to Thermo Fisher Scientific.

Johnson Mattey cited that "This is a further step in delivering our strategy to focus on areas where we can apply our expertise in complex chemistry".

Thermo Fisher Scientific cited that "The acquisition of Alfa Aesar enhances our existing portfolio of chemicals, solvents and reagents to support virtually every laboratory application – from research, to drug discovery and development, to production, In addition, customers will benefit from greater access to these products through our extensive global commercial reach.".