Do you know how sometimes grown-ups make special cookies that they don't want anyone else to copy? Well, companies that make medicine also have special recipes, but they call them "formulas". These formulas are used to make new drugs that can help people feel better.
When a company makes a new drug, they have to test it to make sure it is safe and works well. They do this by experimenting on animals and then on people. This testing takes a long time and costs a lot of money. So, when the company finally gets approval to sell their medicine, they are very happy.
But other companies might want to copy the medicine and sell it themselves. That's not fair because the first company spent lots of time and money to make it. To stop this from happening, the government gives the first company something called "test data exclusivity".
This means that nobody else can copy their medicine for a certain number of years after it is approved. During this time, only the first company can sell the medicine and make money from it. This is like how only the person who makes the special cookies can sell them and make money from them.
So, test data exclusivity is a way to make sure that the company that made the medicine gets to sell it and make a profit, without anyone else copying their hard work.