Which factor can lead to a difference between the theoretical and actual ex-rights price?

The factor that can lead to a difference between the theoretical and actual ex-rights price is market expectations about expansion. The theoretical ex-rights price is calculated based on the assumption that all market conditions remain stable and predictable. However, if market participants anticipate that a company is likely to expand its operations—perhaps due to favorable economic conditions or innovative product developments—this positive outlook can drive demand for the company's shares. As a result, the actual ex-rights price may increase beyond the theoretical price.

Market expectations act as a sentiment indicator, influencing investor behavior. When investors believe that a company will grow or capitalize on new opportunities, they may be willing to pay more for shares than what is suggested by simple calculations based purely on current fundamentals. This divergence reflects the impact of investor psychology and future outlook on pricing, something not accounted for in a straightforward theoretical model.