Stavan Desai has been promoted to head of Americas and Katherine Spenner has been named global chief legal officer of Mosaic Insurance’s transactional liability division.

The appointments come on the first anniversary of the division, which will also be marked by a company podcast.

“Stav and Katherine have been instrumental to the launch and execution of our strategy, and their roles will continue to be vital as we build out our global operations,” said William Monat, Mosaic’s global head of transactional Liability.

“They have provided outstanding leadership and positioned Mosaic well for long-term success in the development of thoughtful underwriting and sound protocols in the M&A sector. They are both deserving of this recognition.”

The unit has undergone a rapid buildout over the past year to meet high demand in the M&A sector. It exceeded $100 million in gross written premium in under 12 months of operation.

Currently, Mosaic has 17 transactional liability professionals in the United States, including global head of tax Jon Hutchens, and eight specialists in London — a tally set to grow this year, as Mosaic opens new offices in Canada, Continental Europe and Asia.

Transactional liability is a cornerstone of Mosaic’s model and specialty strategy, capitalising on its leadership’s successful track record in the sphere.