A license issued to an entity generally continues through a stock sale, while an asset purchase requires the buying entity to hold its own license, with a qualifier, before it can perform the work.
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This matters for fabricators, mechanical suppliers, and any manufacturer that performs field installation. The license is held by the entity and depends on a qualifying individual who passed the examination, so if that qualifier is the selling owner and they leave at closing, the license is at risk regardless of structure. Buyers plan for this by identifying a qualifier in advance, by retaining the seller's qualifier for a period, or by choosing a stock structure specifically to preserve continuity. South Carolina has its own licensing regime with its own rules, which is a live issue for York County companies and for any company whose crews cross the state line to work.