London-based investor relations firm Sodali has announced the acquisition of a US counterpart, Morrow.
The merged entity, Morrow Sodali Global, is now better positioned to target "more global and more outspoken and demanding" shareholders.
The company said its deal would create the "largest independent corporate governance, proxy solicitation, investor relations, capital markets and shareholder services firm in the world".
The merged company will service more than 600 corporate clients across 30 countries with market capitalisations in total of more than $5 trillion (£3.5 trillion).
Morrow Sodali will advise boards of directors and executive management teams on corporate governance, shareholder meetings, shareholder activism, strategic communications, initial public offerings (IPOs) and conduct of multinational equity, debt and merger transactions.
"This transaction brings together two great companies with complementary strengths and expertise that will translate into substantial value for our clients," said John Wilcox, chairman of Morrow Sodali.
Alvise Recchi, chief executive of Morrow Sodali, said: "Investors are becoming more global and more outspoken and demanding.
"With our combined reach into all the principal capital markets, Morrow Sodali is positioned to identify, understand and engage with these investors so that we can advise companies on how to address the expectations and interests of all their stakeholders."