Off the top of my head, large-ish French tech software companies (I would not call them startups at this point) include: Criteo, Dailymotion, Leboncoin, Withings, Parrot, BlaBlaCar, Sigfox... You could also include older companies like Murex or Ubisoft, as well as OVH. You may also want to look at other fields where France is recognized for its expertise (energy, pharmaceuticals...).