Mexican district court justices have rejected Grupo Mexico CEO Germán Larrea Mota Velasco’s bid to dismiss a breach of contract suit by U.K. investment firm Infund LLP. The ruling allows for the longstanding action against the billionaire to proceed to trial in coming months.

Infund alleges Larrea violated a “commercial commission” by refusing to deliver 65 million Series B, Coupon 5 shares of Grupo Mexico securities for which Infund paid $75 million. The 60-year-old Larrea, one of the world’s richest men, personally owns 18% of company shares.

Company public filings from 2006 onward have indicated Larrea retained the disputed shares in his own accounts. In all, these are valued at more than $2 billion, representing 7% of Grupo Mexico’s outstanding equity; they also exceed Larrea’s 51% controlling stake in the firm.