HONG KONG (Reuters) - Pansy Ho, co-chair of Macau casino firm MGM China 2282.HK, has struck a strategic alliance that boosts her control of the crown jewel of her father's business empire, SJM Holdings 0880.HK, sending shares of SJM sharply higher on Thursday.

FILE PHOTO: MGM China Holdings Limited Co-chairperson and Executive Director Pansy Ho attends a news conference at MGM Cotai in Macau, China February 13, 2018. REUTERS/Bobby Yip

Pansy Ho's property to transport conglomerate Shun Tak 0242.HK said late on Wednesday that Ho and four other shareholders of SJM's holding company STDM have agreed to jointly vote their combined 53 percent stake to more efficiently manage SJM.

That puts the alliance’s influence at SJM ahead of that of Angela Leong - the casino operator’s co-chairman and current wife of Ho’s 97-year-old father Stanley Ho. Leong holds 8 percent of SJM.

The news of the alliance helped send shares in SJM up more than 8 percent on Thursday, while Shun Tak rose 6 percent, as investors expected more stability in SJM’s ownership.

SJM and Leong did not have immediate comments.

The move comes ahead of the expiration of casino licenses in the world’s biggest gambling hub of Macau, where SJM and MGM’s licenses are set to expire in 2020.

The concessionaires, which also include Wynn Macau, Sands Macau, Galaxy Entertainment 0027.HK and Melco Resorts MLCO.O, don't have clarity yet on what happens when their licenses expire, starting next year.

About a third the size of Manhattan, Macau is the only place in China where casinos are allowed.

Born into a family that developed a flourishing gambling culture in the southern Chinese territory more than 50 years ago, Ho is spearheading a move to ensure stability, aiming to extend SJM’s gaming concession and maintain STDM as the majority owner of SJM.

In 2011, Stanley Ho sued family members in a high-profile dynastic fight in which he sought to recover billions in assets after a share restructuring he said was done without his consent.

The dispute was settled after two months but gave an insight into the factious nature of Ho’s family and the lifestyle of one of Asia’s wealthiest families.