Simplify the following text for a Grade 4 native English-speaking person.
Original: Along with St. Martin 's Press , Henry Holt , and Farrar Straus Giroux , it is now part of the Holtzbrinck group , now known as Macmillan Publishers .
Simplified: Along with St. Martin 's Press , Henry Holt , and Farrar Straus Giroux , it is now part of the Holtzbrinck group .