The activist investor launched a proxy fight over the Grail acquisition last month, seeking seats on Illumina's board of directors and urging the company to unwind the deal. His resistance to the deal stems from Illumina's decision to close it without approval from antitrust regulators. The Federal Trade Commission earlier this month ordered Illumina to divest the acquisition, saying the deal would stifle competition and innovation. The European Commission, the executive body of the European Union, also blocked the deal last year over similar concerns.