Third Coast Bancshares, Inc. announced on January 16, 2026, that it received demand letters from shareholders alleging deficiencies in the merger proxy statement related to its merger with Keystone Bancshares, which was initially reported on October 22, 2025, but asserts no additional disclosures are needed; the expected financial impact indicates a potential 1.9% dilutive effect on tangible book value per share and substantial earnings growth thereafter.