Simplify the following text for a Grade 9 native English-speaking person.
Original: This often makes attempts to create sequels for a product impossible for various reasons , such as the `` core '' of the studio being fired or replaced after completing a project while the parent company retains control of the copyrights and trademarks .
Simplified: This often makes attempts to make sequels for a product not possible for many reasons . One of the reasons it the `` core '' of the studio being fired or taken over after finishing a project while the parent company keeps control of the copyrights and trademarks .