By Svea Herbst-Bayliss

NEW YORK, Dec 29 (Reuters) - International law firm Cleary Gottlieb Steen & Hamilton has hired an industry veteran to lead its shareholder activism defense practice as more law firms build out capabilities to protect clients facing corporate agitators.

Sebastian Alsheimer is moving to Cleary as a partner from Wilson Sonsini Goodrich & Rosati, where he was also a partner, two sources familiar with the move said. He will be based in New York and will start in January.

Cleary and Alsheimer did not immediately respond to requests for comment.

At Cleary, Alsheimer will advise the firm's corporate clients, including 3M MMM.N, Honeywell HON.O and BlackRock BLK.N, on engaging with activist investors as shareholder engagement and activism defense have increasingly become big business for law firms and banks.

By hiring Alsheimer, Cleary is adding a partner who has represented companies battling corporate agitators and worked with activist investors planning corporate campaigns.

He spent three years at Wilson Sonsini defending clients such as software design company Autodesk ADSK.O and financial software company BlackLine BL.O against Starboard Value and others.

Before that, as a partner at Olshan Frome Wolosky, a firm that traditionally represents hedge funds, he worked with prominent activists Elliott Investment Management and Starboard.

Cleary is the latest blue-chip law firm to beef up its capabilities in countering investors pushing for changes, ranging from refreshing the boards of directors to selling companies.

Earlier this year, Sullivan & Cromwell hired two partners from Vinson & Elkins; Paul, Weiss, Rifkind, Wharton & Garrison hired from Wachtell, Lipton, Rosen & Katz; and White & Case hired from Cadwalader, Wickersham & Taft.

Simpson Thacher & Bartlett recently hired from a bank, adding the former head of shareholder advisory for the Americas at Barclays Capital.

Alsheimer ranks among a small group of lawyers who specialize in activism defense that includes Sidley Austin's Kai Liekefett, Kirkland & Ellis' Shaun Mathew and Sullivan & Cromwell's Lawrence Elbaum.

Alsheimer earned degrees from Harvard, Oxford, Columbia and Yale.

(Reporting by Svea Herbst-Bayliss; Editing by Sonia Cheema)

((svea.herbst@thomsonreuters.com; +617 233 2138; Reuters Messaging: svea.herbst.thomsonreuters.com@reuters.net))